Symptoms of a Bad Camshaft Position Sensor

Updated on June 24, 2017
Dan Ferrell profile image

Dan Ferrell writes about do-it-yourself car maintenance and repair. He has certifications in automation and control technology.

Problems That Can Be Caused by a Failing Camshaft Position Sensor

A failing camshaft position sensor (CMP sensor) can produce a confusing range of problems, depending on the way it fails and the model of the car:

  • On some vehicles, a failing camshaft sensor may lock the transmission in a single gear until you turn off and restart the engine. This cycle may repeat intermittently.
  • If the sensor begins to fail while your car is moving, you may feel the car jerking while losing power.
  • You may experience a noticeable loss of engine power. For example, the engine can't accelerate above 35mph.
  • The engine may stall intermittently.
  • You may notice poor engine performance including irregular acceleration, misfiring, hard starting, or surging.
  • On some car models, a failed CMP sensor will prevent the ignition from making a spark, so that the engine won't start at all.

Camshaft position sensor
Camshaft position sensor | Source

A Camshaft Position Sensor Can Fail Without Warning

An intermittent or complete CMP sensor failure while on the road could be dangerous. It could happen at any time: You are driving on the highway, moving along in fast traffic, when your engine suddenly loses power. There is nothing to do but watch in horror as a vehicle approaching at 70 miles an hour rear-ends you. Not a pretty picture, but it's happened many times.

Other times the driver becomes aware of a failed CMP sensor when the engine refuses to start.

Here, we'll explore the symptoms of a bad camshaft position sensor and what you can do about it. But let's discuss first what the sensor does.

What Is a Camshaft Position Sensor?

The camshaft controls the opening and closing of the intake and exhaust valves.
The camshaft controls the opening and closing of the intake and exhaust valves. | Source

Your engine's cylinder head houses one or two camshafts—a shaft equipped with offset lobes—to operate the intake and exhaust valves. The crankshaft, located in the engine block, drives the camshaft using gears, a timing chain, or a timing belt.

Camshaft
Camshaft | Source

To determine which cylinder is in its power stroke, your car's computer monitors the rotating position of the camshaft relative to the crankshaft position using a camshaft position (CMP) sensor. It uses this information to adjust the spark timing and the operation of the fuel injectors. Thus, the CMP sensor affects fuel economy, emissions control, and engine efficiency.

Camshaft position sensor (Hall-effect type)
Camshaft position sensor (Hall-effect type) | Source

The two most common camshaft sensors you'll see are the magnetic and Hall-effect types. Both transmit a voltage signal to an electronic control module or to the car's computer.

The magnetic type produces its own AC (alternate current) signal (a sine wave), and you can identify it by its two wires. The Hall-effect type uses an external power source to produce a digital signal (a "square wave," on-or-off) and has three wires.

Note: If you are new to all this, you should know that the camshaft position sensor is a different part from the crankshaft position sensor.

How the Sensor Can Fail

Just like every part or component in your car, the CMP sensor will eventually stop working when it's reached the end of its service life, because an internal part, wire, or related component has failed. The symptoms your engine may experience at this point can vary, depending on the type of sensor failure: for example, a problem in the circuit, the connector, the sensor itself, or a related component.

Once your car's computer detects a CMP sensor failure, it will trigger the engine light and store a diagnostic trouble code (DTC) in its memory (see the table below for common camshaft position sensor trouble diagnostic codes).

CMP Codes and What They Mean

Common CMP Trouble Codes
Source of Trouble
P0340 CMP
Circuit malfunction
P0341 CMP
Circuit range or performance problem
P0342 CMP
Circuit low input
P0343 CMP
Circuit high input
P0344 CMP
Circuit intermittent

Camshaft Position Sensor Location

Source

As you may expect, the specific location of the camshaft position sensor varies by a vehicle's make and model. On most models you can find the sensor somewhere around the cylinder head. Look around the top section of the timing belt/chain cover (in the front of the engine) or at the rear end of the cylinder head. Some GM models may have a special compartment for the sensor.

Also, some Mercury Villager and Nissan Quest models locate the CMP sensor inside the distributor housing, as well as some Dodge Ram B1500, B2500, and B3500 series models with gasoline engines.

Depending on the specific model of your car, your engine may have one or more cam sensors.

If you need help finding the sensor(s), check the vehicle service manual for your particular model. You may find a copy in the reference section of your local public library. I highly recommend that you buy an aftermarket repair manual for your specific vehicle make and model (Haynes is a good inexpensive brand) for reference when doing maintenance and small repairs.

CMP Sensor Troubleshooting

If your car computer has already triggered the engine light, you may retrieve the code (the DTC) using a code reader or a relatively inexpensive scan tool. If you don't own a code reader and can't afford to buy one, and you still can drive your car safely, just go to a nearby auto parts store that retrieves DTCs for free.

After confirming a CMP-sensor related trouble code, it's worth doing some simple tests. A trouble code pointing to a potential CMP sensor failure doesn't necessarily mean that the sensor itself is bad. You may be dealing with a wire, connector, or related component failure that you can fix yourself.

However, confirming the good or bad operation of a camshaft sensor may require a scope. A failing sensor signal, for example, may be hard to check without special equipment. Still, you can do some simple checks in your garage using a digital multimeter (DMM) tool.

  • First, check the condition of the sensor's electrical connector and wires. Unplug the connector and check for rust or contamination, like oil, that is interfering with good electrical contact. Then check for wire damage: broken wires, loose wires, and signs of burns caused by nearby hot surfaces. Also, make sure the sensor wires are not touching spark plug wires or ignition coils, which may interfere with the sensor's signal.
  • After these checks, use a digital multimeter that can test either alternate current (AC) voltage or direct current (DC) voltage, depending on your particular type of camshaft position sensor. You'll also need the correct electrical values for your particular type of sensor. You may find this information in your vehicle repair manual.
  • With some sensors, you may back-probe the wires through the sensor electrical connector.
  • If this isn't possible, see if you can unplug the sensor connector and attach a strand of copper wire to each terminal on the connector. Then plug the connector back in so that the two strands stick out through the connector's housing.
  • Another testing solution is to pierce through each wire using a pin, being careful not to short out the wires during your tests. If you use this last method, use electrical tape to cover the pin holes on the wires' insulation after you're done with your tests to prevent corrosion from creeping into the wires.

Testing a Two-Wire Sensor:

  • If you have a two-wire, magnetic-type CMP sensor, set your multimeter to "AC volts."
  • Have an assistant turn the ignition key on without starting the engine.
  • Check for the presence of power flowing through the circuit. Touch one of your probes to ground (any metal part on the engine) and the other probe to each one of the sensor wires. If neither wire has current, there's a failure in the sensor's circuit.
  • Have your assistant crank or start the engine.
  • Touch one of your meter probes to either one of the sensor wires and the other probe to the other wire. Check your meter display and compare your reading to your manual specifications. In most cases, you'll see a fluctuating signal between 0.3 volts and 1 volt.
  • If there's no signal, you have a bad CMP sensor.

Testing a Three-Wire Sensor:

  • Once you identify the power, ground, and signal wires using your vehicle repair manual, test the sensor's circuit by setting your multimeter to "DC volts."
  • Have an assistant turn the ignition key on, but don't start the engine.
  • Touch the black probe on your meter to ground (a metal bracket, bolt, or metal surface on the engine itself) and the other probe to the power wire. Compare your reading to the specification in your manual.
  • Have your assistant crank or start the engine.
  • Touch the signal wire with the red probe from your meter and the ground wire with the black probe. Compare your reading to the specification in your vehicle repair manual. If the voltage signal is lower than the specification, or no signal comes out of the sensor, most likely the sensor is bad.
  • Remove the sensor and inspect it for signs of physical damage or contamination.

Check the video below to see how you can perform these tests using a test light and a multimeter. It'll give you an idea of the nature of the tests too. If you can't find anything wrong with the sensor or its circuit, it's possible you may have an intermittent failure or a failure in a related component. For example, you may have a weakened or overstretched timing belt or timing belt tensioner. A worn-out belt can prevent the camshaft and crankshaft from synchronizing, causing the CMP sensor to send the wrong signal.

Testing a Camshaft Position Sensor

Sensor Replacement and Cost

If you've confirmed that the camshaft position sensor is bad, you may want to replace it yourself. On some vehicle models, replacing the sensor is just as easy as unplugging the electrical connector, unscrewing the mounting bolt, pulling the sensor out, and installing a new one. On other models you may need to remove one or more components to gain access to the sensor (as you will see in the next video).

Check your car's repair manual for instructions on how to replace the sensor on your particular vehicle model.

Expect to spend anywhere between $30 and $100 (or more) for the sensor itself, depending on your vehicle model. If you take your vehicle to a car shop, you may be looking at $100 or more in labor expenses too.

Replacing a Camshaft Sensor (Nissan Altima)

The symptoms I discussed above are not clear signs that your CMP sensor is bad. Still, if you recognize one or more of these symptoms, try to diagnose the problem as soon as possible. The last thing you want is to get stuck in the middle of the road. Start by getting the trouble codes from your computer memory, and, if necessary, testing the sensor with the help of your vehicle service manual. Sometimes you can determine the cause of the problem and fix it yourself without spending too much time and money.

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    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      7 days ago

      Hi Anita,

      This video may help you find it.

      https://www.youtube.com/watch?v=cObLduaH-L0

    • profile image

      Anita 

      7 days ago

      Where IS MY crank shaft positioning sensor on 2001 pathfinder

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      11 days ago

      There could be some mechanical damage. You need a diagnostic form a shop. Check the starter motor, make sure it's correctly installed. You may need to pull it out and see if it's still in good condition. An auto parts store may check it for free.

      Good luck

    • profile image

      Fred 

      12 days ago

      Sir,my car is having issues, my bottom plate bust on my engine oil pour out totally.trying to manage the vehicle to machanic I was told my metal was already bad we change the metal, fixed up the car but now am experiencing problem of sudden breakdown of the vehicle when moving...Also I hear cracking noise when I try to fire the vehicle

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      3 weeks ago

      Hi Amarjit,

      In general, the camshaft sensor works with the crankshaft sensor to send information to the ECU,(car computer), to synchronize some operations of the fuel injection system and knocking control. A bad camshaft may also affect spark.

      The camshaft sensor may failed due to mechanical damage, failing to 'read' the enconder wheel (bad wheel-tooth?), electical circuit malfunciton of the sensor.

      Hope this helps.

    • profile image

      Amarjit 

      3 weeks ago

      When I drive suddenly car engine of and try start not starting fuel, plug, crank sensor is working but camft sensor not working because of iwant to kwow that camft sensor is bad engine start not working this my question

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      2 months ago

      Hi Sarah,

      The code points to a problem with the camshaft circuit. There could be an actual problem with the circuit or the computer. Usually, a problem with the circuit will manifest as drivability probems - loss of power, misifres, and - depenidng on model - hard to start issues. Either way, its a good a idea to take a look into it.

      Good luck

    • profile image

      Sarah 

      3 months ago

      My 2005 dodge neon check engine light came on a couple days ago and when I checked the code it was P0340. I haven't had any issues driving or felt anything different. Could the code just need to be cleared, or is there really something wrong?

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      3 months ago

      Hi Yep

      It is possible a faulty camshaft can cause a misfire. Other common possibilities are a dirty or bad fuel injectors, faulty oxygen sensor, an ignition coil, and a faulty EGR valve or clogged passages. If you have an old model, you also want to consider a clogging cat converter and burned exhaust valves.

      Good luck

    • profile image

      Yep 

      3 months ago

      Got a p0300 code could a failing crank shaft sensor be the problem,already replaced the vac lines,cleaned intake manifold,idle sensors,spark plugs,tune up

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      3 months ago

      Hi MG,

      It's possible the first time when the head gasket was replaced there were other damaged that wasn't diagnosed, hence the subsequent loosing of power and stalling - (compression loss?) - You need to have a mechanical condition diagnostic from another shop, if you are still going to the same one - just to see their opinion on the repairs that were done the first time - (incomplete? ) - what caused the cam lobes to burn.

      Good luck

    • profile image

      Margarette Groenewald 

      3 months ago

      My Defender 90 had head gasket failure in June 2017, which was replaced. Since then the car started loosing power, loss of engine power and stall intermittently. In Nov 2017 diagnostic test was done after engine failure on highway, filters was changed, fuel system was checked and cleared, ignition key was changed and, car was also fully checked for the long road, In March 2018 replaced engine oil etc, , Filters etc, looked at engine surging & poor idle and replaced housing fuel filter assy. April 2018 hear vibrating noice, car looses power and knocking noise. Just been informed that there is damage to the exhaust cam lobes, 3 lobes burnt. Any views on this please

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      3 months ago

      Check the connectors and wiring for corrosion or damage. Also, some models will only take OEM components and will refuse to work otherwise.

    • profile image

      Jason 

      3 months ago

      Just wondering what would be the reasoning if you put a new sensor in and the car still doesn't work and the OBD reader still reads the same thing saying that the sensors not working please help

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      3 months ago

      Hi MB,

      It's possible there is a problem with the ignition module or even the crank sensor. Scan for codes first, if there aren't any, have the ignition module checked.

      Good luck.

    • profile image

      Mark Brandenburg 

      4 months ago

      I have a 99 Chevy Silverado with 5.3 engine, when the engine is cold it cranks easy (when I first crank it in the morning) but when the engine is hot or I've driven it for a while and turn off the engine and let it sit for a while then try to crank it again it is hard to crank, so far it has always started back up. I put a new fuel pump on it and timing sensor but it didn't help. What do you think I need to do next?

      Thanks.

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      4 months ago

      Hi Kenneth,

      It's is possible. Read the trouble codes from the ECM for pending codes if necessary, and test the sensor.

      Good luck

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      5 months ago

      Hi Steven

      Have you checked for carbon buildup in the throttle body-valve, and blocked passages for the IAC?. A vacuum leak is another possibility.

      Good luck

    • profile image

      steven meekins 

      5 months ago

      I have a 1995 buick lesabre 3800 engine OBD1 with an OBD-2 connector scan port and can't read engine code...idles too high when cold, too low and intermittent stall when hot, replaced crank sensor, idle motor,TPS, cleaned MAF, good fuel pressure and vacuum....ready to try MAP sensor and cam shaft position sensors...any thoughts..? meekinssteven.meekins@gmail.com to any who have conquered this before. Thanks.

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      5 months ago

      Hi John q

      It is possible you have a failing battery, have it checked and check the connections at the starter for corrosion. A failing starter can do this as well sometime when hot - coil may have cracked. It'll work fine when cold but will struggle when hot.

      Good luck

    • profile image

      john q 

      5 months ago

      hard starting when engine warm,honda civic 2.

      when this happens occasionally eml and showing code P0339, crankshaft sensor which i have replaced, but problem persists.

      Could problem be due to weak battery?

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      5 months ago

      Hi JM

      It could be a bad sensor or bad connection.

      Also, check for DTCs or pending codes.

      Good luck

    • profile image

      Johnny Mora 

      5 months ago

      Hi, I have a Nissan Altima 07' 3.5 My temp Gauge fluctuates goes all the way up on incline while on the road. Then temp goes normal on decline but temperature gauge reads hot on long drives. I've changed the Radiator, Thermostat & still does the same...I did research says maybe a thermo sensor?

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      5 months ago

      Hi DC

      My first guess would be a bad connections at the exhaust.

      Good luck

    • profile image

      Darrell crum 

      5 months ago

      what will make a 5.7 Vortec engine labor like a diesel

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      5 months ago

      Hi James,

      Intermitent faults are hard to diagnose, but the code is pointing to a faulty crankshaft position sensor or circuit. Still, it's a good idea to pull the sensor and check for shavings or other contamination that might be interrupting sensor operation. Also check the reluctor wheel

      Good luck

    • profile image

      James 

      5 months ago

      i have a Mercedes e300 w211 272 engine 2008 model. I had a fine drive all day since morning but at some point the check engine appeared and upon parking the car refused to start the engine at the evening while leaving office in the evening. The next day the car started fine and upon taking it for diagnosis the error code p0336 had registered.

      it now three days and the car has no issues.

      kindly advise on the possible cause of car failure.

      thanks

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      6 months ago

      Hi NH,

      You might want to check oil pressure. On some models the computer will prevent you from starting the engine when oil pressure drops below a certain threshold.

      Good luck

    • profile image

      Nikita Hirsch 

      6 months ago

      hi i have a 2006 dodge stratus i drove around fine all days but when i came home it stalled i tried starting it back up it wouldnt no engine light came on but odd enough the oil light came on but i got an oil in less then a month it does idle low i live in minnesota so it really cold right now just not sure what to check cause i dont want to fry my starter

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      7 months ago

      Hi Jorg,

      It may seem that the spark or fuel is being cut. You should try to retrieve any trouble codes from the computer memory to start a diagnostic, since the check engine light is coming on.

      Good luck

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      7 months ago

      Hi B123,

      There may be some trouble with a sensor.

      Check for carbon build up inside the throttle body and under the trhottle plate.

      Have you scan the computer memory for trouble codes.

      Check it even if you don't see a check engine light on.

      Good luck.

    • profile image

      Babybo123 

      7 months ago

      Have problem with my infinti since cold weather started idle rough and stalls have to keep revving the engine up after warm up its fine

    • profile image

      Jorg 

      7 months ago

      Hi! I have a problem with a opel Vectra 2.0 2001 mod. When i drive, the car will suddenly shut down and the enginge light comes on. The only way i can start the car again is to take the key out, and then in again of the ignition. After this the car will run smootly again. The problems have occured several times.

      I have replaced the crankshaft sensor but with no luck. I wonder if it could be the camshaft position sensor that causes this? Any tips would be appreciated!

    • profile image

      Mason 

      7 months ago

      Hi Penny, I too had a similar problem with my car, where the engine would shutdown when coming to a stop. It would occur without warning and the check engine light was never activated. This happened to me 3 times over a 5 week period before I realized the car was low on oil and leaking too. Check/and repair leaks asap and top up your engine oil sooner.

    • profile image

      Antonio 

      7 months ago

      I have a 97 Buick Skylark limited v6

      What is the fastest way fixing this?

    • profile image

      Alexis Velazquez 

      7 months ago

      I have a 2011 Kia sportage, it seems that a Camshaft Position Sensor B Circuit (Bank 1) went bad but my question is where is this sensor located? I know that there are two sensors (total) I have found one but not the other. Can you point me to any resources where I can find this info. Thanks Much appreciated.

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      7 months ago

      Hi penny

      A bad crank or cam sensor can make the engine stop when failing. But low oil pressure can do the same thing on some models.

      Have you checked for an oil leak? The fact that it had a normal level in November and a few days later was very low seems suspicious.

      Keep an eye on the level. If you suspect a leak, have it checked. This might be the other reason (?) why the engine stalls.

      Good luck.

    • profile image

      penny 

      7 months ago

      I just had to get a cam position sensor replaced. It was so confusing as my car stopped DEAD in traffic, very scary. Got it towed. The codes showed CRANK position sensor and CAM position sensor. The mechanics put in the CRANK one. Two weeks later, it stalled again. Took it back. Code for CAM came up but when they tested it manually it all still worked so they said I did not need a new one and to try driving it again. So a third time 2 weeks later it stopped AGAIN. very scary again. So I took it to the Nissan dealer this time as I wanted to be sure. They replaced the CAM position sensor and said the car was very low on oil. I only had an oil change done in June (it is now December) and only 4,000 K since then. It was not low in end of November when I took it to the first garage. Bottom line I am very confused-and I hope the car is not going to stall again as I am afraid now to take it on the highway and will only drive it around town, I don' t have any confidence these are what was causing the problem as when they tested manually it was ok and your article also says it could be other things. This is on a Nissan X trial by the way which has been until now a fabulous trouble free car.

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      7 months ago

      Hi Millie,

      Sometimes heat can do this to sensors. You may be lucky using some penetrating oil on the new one but be careful not to get any oil on the surrounding belts.

      You may need to carefully drill the stuck sensor out.

      Good luck.

    • profile image

      Millie 

      8 months ago

      Could magnetic sensors sticking can come from bad oil or transmission oil need to be changed?

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      8 months ago

      Hi Craig,

      Possibly the camshaft or crankshaft is not seated correctly. Some sensors come with a spacer to give the proper distance when installed. Some people remove this thin paper (?) spacer. Make sure the sensor(s) are seating correctly. If you removed the spacer or fell before installation, the sensor may have the sensing surfaced burned. Remove it and check it.

      Good luck

    • profile image

      Craig 

      8 months ago

      Hi There,

      I have a 1999 Nissan Wingroad that is giving me some trouble. The first thing i noticed is the tacho got a little jumpy. A little while after (a couple of weeks or so) the car would start surging and losing power when trying to accelerate at low revs. A couple more weeks after that the engine check light came on. Have had it looked at by the mechanic and they said the code suggested a cam/crank sensor problem. I have since purchased a pair of aftermarket sensors and after installation the car would crank but not fire. Help. Do i need to erase the fault codes before I carry out the installation? It seems unlikely that both replacement sensors are faulty.......

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      9 months ago

      Hi Nick,

      It seems like there's an ignition related issue, probably a misfire showing up under load. Check the plug wires for damage. One of them might be "breaking" when you accelerate.

      See if you can accelerate while firmly depressing the brake pedal and the tranny on Drive. If the engine sputters while accelerating, the problem is one of the wires or related circuits (ignition coil?).

      Good luck.

    • profile image

      Nick 

      9 months ago from St. Pete

      Hello Dan and wow... thanks sooo much for helping everyone out here! A lot of time on your part!

      Speaking of parts lol, I got the code check done and it was a bad camshaft senor on my girlfriends 03 Murano. I bought a pack to replace both camshaft sensors and the crankshaft sensor. I replaced both and now the problem is worse... the car will (most of the time) start up but when I give it gas and the rpm gets above 2000 the car jumps and stutters and won't accelerate. Do you know what is going on with that? I erased the codes and it still was happening. Even disconnected the battery to reset everything.

      I am going to buy some MAF cleaner and give that a try, but anything on your end you think is happening?

      Again, thanks!

    • profile image

      Nick 

      9 months ago

      Hello Dan and wow... thanks sooo much for helping everyone out here! A lot of time on your part!

      Speaking of parts lol, I got the code check done and it was a bad camshaft senor on my girlfriends 03 Murano. I bought a pack to replace both camshaft sensors and the crankshaft sensor. I replaced both and now the problem is worse... the car will (most of the time) start up but when I give it gas and the rpm gets above 2000 the car jumps and stutters and won't accelerate. Do you know what is going on with that? I erased the codes and it still was happening. Even disconnected the battery to reset everything.

      I am going to buy some MAF cleaner and give that a try, but anything on your end you think is happening?

      Again, thanks!

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      10 months ago

      Hi Randy,

      Have you checked the codes? Scan the computer, there may be some pending codes if the light hasn't come on.

      There may be a lean condition. Try spraying some carburetor cleaner around the intake and vacuum lines. See if you find any leaks.

      Does the TPS (throttle positioning sensor) needs adjustment? Check for proper operation.

      Good luck

    • profile image

      Randy 

      10 months ago

      I have a 2000 B2500 mazda pickup I replaced the spark plugs, the spark plug wires, air idle value, and the idle positioning sensor and when I start it for the first time in the morning it sounds like one of the pistons are not firing once I get going the rpm's go way up when I push in the cluch to change gears it seems like once it warms up the rpm's go down a little bit but are still above normal just wondering if it could be the cam sensor or the crank sensor please help

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      10 months ago

      Hi Lee

      Sorry to hear you were caught on the road with this issue.

      You seem to haave a "naked" wire that is causing you a short, hence the smoke. There's too much current going through that circuit. You need to locate that short first. That may be related to the other issues.

      Good luck

    • profile image

      Lee 

      10 months ago

      My car had a bad ground and since the ground was fixed the cam angle position wire connectors start smoking after 20 minutes, also the car stalls randomly as I change gears with sharp drops in rpm, I'm currently on the side of the road and will advise on the multimeter test and wire inspection, any thoughts?

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      10 months ago

      Hi Andrew

      The fault may be caused for:

      * some needed maintenance service needed,

      * you may have a failing alternator (have it checked, if possible) a bad diode may be the cuase

      * or there's actually a failure in the camshaft circuit

      in the last case, it's not a good idea just to replace it, you need to:

      * make a visual inspection of wires and connectors for the camsahft

      * use your vehicle repair manual to check-test the camshaft sensor.

      * do the same with the crankshaft sensor

      Good luck

    • profile image

      Andrew 

      10 months ago

      Hi Dan

      My opel vectra 2.8 v6 2006 has faults p0340 and p0345. I have noticed the car started fine when cold and once warm it thoughts up the spanner light. What are the chances of both sensors failing at the same time? The car stalls under load and then has trouble turning over.

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      10 months ago

      Hi Jim,

      It's hard to tell without some tests, but I would check the throttle body first. Make sure there no carbon deposits. Give it a good clean, over and under the choke valve and air horn body. Get rid of all carbon deposits.

      Also, you want to check the idle air valve. You may need to remove it and look for carbon deposits as well around the passages.

      Check the idle valve, make sure it is operating correctly. You may need the repair manual for your model to test it.

      Good luck.

    • profile image

      Jim 

      10 months ago

      Hello Dan,

      I have a 2014 Nissan Altima and have an issue.

      1. Starts fine but runs rough.

      2. When engine is warm car starts fine but when put in gear stalls.

      3. When engine is cold, I can start, rough idle, and put in gear and it will move.

      4. check engine light it not on.

      My thinking is the a sensor is bad, either the cam or crank but i'm not an expert. Do you have any thoughts?

      My thinking is

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      10 months ago

      Hi Phil,

      You seem to have a pre-ignition problem - something is causing the air-fuel mixture to ignite before it should. Usually this points to bad ignition timing, but because of the previous lean condition (vacuum leak), I'm wondering if there's too much carbon build up in the chambers. Also, was there an overheating problem before?

      * Check the ignition timing to make sure it is still good (not too advanced).

      * Check the usual ignition suspects - spark plugs and wires + injectors, (injection system) for carbon deposit source.

      * Also, make sure you're still using the recommended fuel for your model.

      I'm guessing the cam "fault" was intermittent and it triggered the DTCs on and off - hence the 133 faults (?).

      Good luck

    • profile image

      Phil 

      10 months ago

      Hello Dan

      Had my 96 BMW 318ti on a computer today it showed up 133 repeated faults on the cam sensor. I went out and bought a new one which turned out to be a dud and the car wouldn't run at all. Whilst I had the plenum chamber off (need this off to get to the sensor's plug unfortunately!) I noticed a split in the end of a pipe from the air intake pipe to the injectors. Luck would have it it was at the end of the pipe so trimmed it back to good rubber and refitted it. I refitted the old cam sensor to get back to the spares shop to exchange the sensor which they didn't have any more of (just my luck!). Strangely the symptoms I was experiencing have disappeared so I am taking a guess that the vacuum pipe was causing them. That's good BUT i have noticed a pinking sound under load AND there is the question of the 133 faults? I am debating wether or not I do have a faulty sensor what's your thoughts and if not what else could cause the pinking sound on a modern engine?

      Thanks Dan

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      10 months ago

      Hi Jeff,

      Yes, it could be any of those things. Have you check for DTCs (trouble codes)? Start there. Usually a bad crankshaft or camshaft will trigger the check engine light. If the injectors, fuel pump or another system device isn't working properly, the engine might not start.

      Good luck

    • profile image

      Jeff. 

      10 months ago

      Hi dan.

      I can't start my freelander 2 2.2 td4 2007.

      Cranks over but won't start. Changed the battery and the diesel fuel filter bled it all no air in system.

      Been told it could be the crankshaft / camshaft sensor / fuel pump.

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      11 months ago

      Hi Sharon,

      Did you erase the original trouble code after replacing the cam sensor? Otherwise it's going to stay in memory.

      Also, check the connections for contamination, dirt, oil, etc.

      If you have a digital multimeter, you may want to check for incoming voltage and the signal. Your vehicle repair manual may give you the steps for this. You can get an inexpensive, aftermarket manual for your model through Amazon or your local auto parts store.

      Good luck

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      11 months ago

      Hi Augie,

      How do you know it is damaging the sensor? - Usually oil leaks around the sensor will ruin it. Make sure there are no leaks around.

      Also, a failure of the timing belt, mass air flow sensor, and crankshaft position sensor can trick the computer into "detecting" a fault in the camshaft sensor.

      Hope this helps, good luck

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      11 months ago

      Hi Terra

      You may need to clean up the trouble codes in the computer memory. If you disconnected the battery while replacing the sensor without using a memory saver, it might take a few weeks for the computer to relearn the best driving strategy for the engine.

      Good luck

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      11 months ago

      Hi Terra,

      You may need to erase the sensor TC from your computer memory. You can do this with a scanner.

      Also, if you disconnected the battery without using a memory saver while replacing the sensor, your computer may have lost the adaptive learning strategy. It may take some time of driving (miles) before it relearns the best engine operating conditions for your vehicle.

      Good luck.

    • profile image

      Terra 

      11 months ago

      I replaced my camshaft sencor but it still show up on car computer and my car still doesnt run right. What else can I try.

    • profile image

      Augie C 

      11 months ago

      Hi I have changed my Camshaft Sensor A Ciscuit Bank 2 3 times in one week works for 2 days and damages the sensor. I got it at Pep Boys not sure if something else is causing this to fail all the time. Will have to buy the Original one form Nissan

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      11 months ago

      Hi Pete,

      Your first step is to scan your computer for trouble codes. If there's a problem with the cam sensor, most likely the computer got a code. Probably your local auto parts store will retrieve the codes for you.

      If there's a sensor for it, try to troubleshoot the sensor. My guess is that the repair manual for your make and model will have the procedure.

      Get an aftermarket repair manual, they're inexpensive and very useful.

      Good luck

    • profile image

      tomonator 

      12 months ago

      Hi Chaps .. any advice is fantastic of you :)

      I have a vaux astra 1.7 deisel estate 2003

      I have been told my symptoms relate to the cam shaft sensor .

      it will start no problem but cuts out after about 10 seconds ..turn it off then same again .. as if its stalling ... everything mechanical seems fine .. but im eager to learn something and sort it myself if possible

      thanks Pete

    • profile image

      Dunnie 

      12 months ago

      Thanks Dan.

      I will try what you have advised above. The stater motor seems to be working fine because it always cranks with the same sound even when the car is unable to start. Whenever i experience this hard start, the sound of the exhaust will sound like a lazy sound, not active like the normal one. It always sound like I am using a big pipe straw to blow air instead of the small normal one. During the cranking the engine will sound like its about to ignite and eventually dies just after. I will give feedback after .

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      12 months ago

      Hi Dunnie,

      Hot related issues sometimes are hard to diagnose.

      Try some of this test/troubleshoot tasks.

      Next time the engine is hard to start open the hood and let the engine 'breathe' for a few minutes and try starting the engine. If it does, you might have issues with the starter motor.

      (just by curiosity, did your mechanic check for gas vapor lock?)

      Also, test the air temperature and cooling sensors.

      Good luck

    • profile image

      Dunnie 

      12 months ago

      Hi guys. I am driving a VW polo Comfortline 2012. I have been experiencing hard start since last year in September especial during hot weather conditions. In the morning where temperature is cool the car starts quite well, but if i leave the car until 11:00 or 12:00 without starting it the car wont start until late in a day after the sun has set. I usual do kick start whenever i experience this, I took it for service to VW but they said everything is completely fine, noting they could find using the scanner(Comp). Sometimes it goes like this, if I drive for say 20 kilos and park at a parking slot which is exposed to the sun for 30 minutes, the car wont start. I have to push it or wait until it cools down completely. I am not sure what could be the problem while the VW dealer could not spot anything.

      Thanks for your assistance in advance.

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      12 months ago

      Hi preston,

      On some models the computer won't let you drive. Other models you'll experience hard starting issues but you'll be able to drive. Still, you may experience stalling - this makes it unsafe. The engine may stall in the middle of the road. Safer to replace it ASAP.

      Good luck

    • profile image

      preston 

      12 months ago

      can operating without the sensor damage your engine? 2002 gmc envoy

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      12 months ago

      Hi Robin

      On some models the computer will lock the engine if a overheat condition exists. A failed temp sensor may cause this. This is to save the engine from catastrophic failure.

      Also, did you check/replace the CPS.

      Good luck.

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      12 months ago

      Hi, Michele,

      If you disconnected power (battery) to replace the sensor, it might give you some trouble. Make sure to erase the trouble code for the cam sensor. It probably gonna take a while for the computer to relearn the best driveability strategy for your model. Also, make sure you didn't unplug a vacuum hose or connector by mistake.

      Good luck

    • profile image

      Michele 

      12 months ago

      I have a 2010 Audi A4 the service engine light came on about a month ago the code reader said the camshaft sensor was bad but the car seemed fine two days ago the car didn't start in the first try then did I pulled out and the car wouldn't go I hit the gas hard and it went then stalled the. Ad started back up but wouldn't go the service engine came up again and the code reader said the camshaft sensor we replaced it but now the car won't start. We also replace the crankshaft sensor a few months ago. Please someone help

    • profile image

      Robin 

      12 months ago

      I have a 96 chevy 3500 with 454 engine. I had a dtc for the camshaft position sensor. One day the truck wouldn't start. It would crank but not start. Had no communication with ecm. A new ignition switch was installed and it started. Drove 15 min trying to get home and the truck lost power then died. After I came to complete stop I tried restarting and engine locked up. Temp gauge instantly shot to max hot when lost power. Was engine lock up caused from sensor?

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      12 months ago

      Hi Darcy,

      Check the EGR valve, it my be stuck closed. Other possibilitiy is a fuel pump or ignnition coil starting to fail. They will usually run good when cool until they reach temperature.

      Gool luck.

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      13 months ago

      Hi Ron

      You may need to clean the computer's memory (you can do this with a scan tool), or there might be more trouble codes in it.

      Good luck

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      14 months ago

      Hi,

      Have you scanned the computer memory for trouble codes? Make sure the sensor is your problem and try to troubleshoot it. The vehicle repair manual for your make and model will help you.

      Good luck

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      14 months ago

      Hi Adrian,

      probably this link will help you locate the sensor

      http://www.justanswer.com/chevy/2jdyr-cam-sensor-l...

      Good luck

    • profile image

      Help Dan 

      14 months ago

      I changed timing chain and both gears. I figured it jumped timing. Im new to cam shaft position sensor. Please help.

      Thanks.

    • profile image

      Adrian 

      14 months ago

      Hi , I have a 2000 Chevy Silverado 1500 4.8 and I cant find the cam shaft position sensor. I was driving and truck just thumped and turned off. Now wont start and misfires. Can someone tell me location of cam shaft position sensor ?

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      14 months ago

      Hi HM,

      Yes, you might want to check the alternator. Your repair manual should give you a few simple tests you can do on your own.

      Good luck

    • profile image

      Haziq M 

      14 months ago

      Hi Dan, thanks for the feedback. Checked the battery. Its shows around 12v. Even I revved up to 3000rpm. Maybe the alternator already weak. Correct me if im wrong. Thanks.

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      14 months ago

      Hi HM,

      The DTC may be pointing to a circuit malfunction.

      Make sure you have a good, charged battery and no problems with the starting system (connections and starter motor)

      Check the sensor circuit -- harness (opens or shorts), poor electrical connection.

      Good luck

    • profile image

      Haziq M 

      14 months ago

      Hi. What if the DTC tells Camshaft signal incorrect/not recognize.

      Merc E230 W210

      Thanks.

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      15 months ago

      Hi Pat,

      Apparently you have a fault in the circuit, check the wires that connect to the sensor for cuts or damage. If you feel comfortable using a digital multimeter, test for ground, power and signal voltage to the sensor. The problems seems to be more likely in the circuit. But don't discard a faulty sensor.

      Testing will be easier if you have the repair manual for your car make and model. You can find relatively inexpensive aftermarket manuals at Amazon and your local auto parts store.

      Good luck.

    • profile image

      Pat Taillon 

      15 months ago

      2003 Cadillac cts. Turned the key and vehicle to seconds after releasing key to start. Approx 3 simular starts within an hour the check engine light came on. Took to auto store for diagnosis code P0343 showed up. Camshaft position sensor A Circuit high input B1 reading. Hoping for opinion on sensor or cause that would trigger sensor. Thanks in advance. Pat

    • profile image

      adnan 

      16 months ago

      thanks

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      17 months ago

      Hi Patricia,

      Can be just coincidence, but your mechanic should be able to test the sensors to make sure they are working correctly before replacing them. Maybe something got disconnected during the service procedure that trigger the engine light.

      Good luck.

    • profile image

      patricia 

      17 months ago

      having issues with my car passing emissions it is saying cam shaft sensor out of timing and also speed senor just replaced valve cover and new plugs this didn't arise until we done this

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      18 months ago

      Hi nyasha

      Have you checked for a spark leak? Also, check the boot and the spark plug to see in which condition they are. Make sure four cylinder wire is receiving the command from the computer to fire.

      Good luck

    • profile image

      nyasha_nyabango@yahoo.com 

      18 months ago

      hi i am working on a toyota 3rz engine , cylinder no 4 is not contributing any power to the engine what can cause that. all valves are closing the compression is ok . the ht lead is supplying the spark . but when i pull out the ht leadf it shows there is no contribution

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      19 months ago

      Hi Dam

      Yes, the CMP sends a pulse signal to the computer when cylinder 1 is about to reach TDC on the compression. This is to synchronize and sequence the injectors.

      Have you check for any computer trouble codes? If you get a code for the CMP, first check it to make sure the sensor is the one causing trouble, then check the circuit (connectors and wires) betwen the sensor and the computer.

      Good luck.

    • profile image

      Dam 

      19 months ago

      On a 98 ford explore V6 does the camshaft positioning sensor control The fuel injectors? I'm getting fuel when I turn the key on when I crank the motor fuel pump is not pumping in my Fuel injectors aer not pulsing?

    • profile image

      Fahad 

      19 months ago

      HI, i have been looking for the soulutin for my Audi TT 1.8 coupe 2003 A/T..

      i bought this car whit engine light ON, i did scan and the code i forgot, cause it was long time ago and car was still running.. i cleared the code and it cam back after next start.. later on it becomes difficult to start the car sometimes, after 2,3 cranks it get starts... i kept it driving this way.. i remember it went off once while driving.. but usually i had trouble to start the car in one self... i parked this car for few months.. batter went dead and car didnt started again.. i changed the battery still its cranking but not starting up... anybody has any idea??

      i am about to replace camshaft position sensor and crank sensor soon because on youtube and other sites recommends things like this happen if one of these sensors are not working..

      by the way i did the scan again last week it was code P017 something i cleared the code but because i cant start the car i dont know what was the code for...i cant see any code unless the car starts again..its on but no error until it gets starts..(my bad)

      what are your suggestions??

      Thanks

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      19 months ago

      Hi Grizzly,

      There could be seeral reasons for a lean code, if you're not getting a specific circuit malfunction DTC from the computer, check for a possible vacuum leak, dirty MAF sensor, and also check the air filter housing and assembly for a leak after the MAF sensor (unmetered air).

      When was the last time you changed the fuel filter (every year or two is the most recommended) a clogging filter can give you this type of problem.

      (Sorry for the late response, your comment was wrongly caught by the spam detector"

      Good luck

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      19 months ago

      Hi Dilly,

      Sometimes when a pump is on the way out, it'll cut out after a few minutes of driving. And the same thing happens some times with the ignition control module. Let them cool down and they'll come back to life. It can drive you crazy. But after some time, they'll just die.

      (Sorry for the late response - the comment was wrongly cut by the spam detection robot)

      Good luck

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      19 months ago

      Hi Kelly,

      When your car computer stores a DTC (diagnostic trouble code), it only points to the circuit where it detected a poetntial malfunction. In this case, the camshaft sensor circuit. It doesn't necessarily meand the sensor itself is bad. You still need to verify whether the sensor is bad, or the circuit that makes the sensor work. You need to troubleshoot the circuit and the sensor to see where the fault is located.

      If the gas cap is not closing tight, yes, it could trigger the check engine light. You might want to replace the cap with a new one and then check to see if the light goes on. Otherwise, have the sensor and circuit checked.

      Good luck.

    • profile image

      KellyT 

      19 months ago

      Hello, I replaced my Camshaft Sensor as my engine light came on and the code said it was the sensor. However, after driving it for a few days, the engine light came back on... Camshaft sensor again. What could cause this? Also, my gas cap doesn't click anymore... could this also cause my engine light to come on??? Thanks in advance for any help!

    • Dan Ferrell profile imageAUTHOR

      Dan Ferrell 

      19 months ago

      Hi Thomas,

      Yes, usually on electronic components try to buy brand quality replacement or OEM. You'll save yourself from a lot of trouble, even if you spend a little more.

      Glad to hear the car is back on the road.

      Good luck.

    • profile image

      Thomas Falater 

      19 months ago

      This happened to my Mercedes and I checked the wires, did all the tests, and replaced my camshaft position sensor with a $30 one. Two days later the check engine light came on with the same error message 'camshaft position sensor', although the engine ran fine. I bought a Bosch brand position sensor for $100 and installed that and it solved the problem. The check engine light stayed off. Don't buy the cheap sensors. Thomas Falater

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