How to Change Spark Plugs & Coils: VW & Audi 1.8T
Save Money and Do It Yourself
Before I started this write up I gave my local VW/Audi dealership a call to get a general idea of what they are charging to change spark plugs. For this simple task I was quoted a price of $161 dollars for parts and labor. Really $161? Why not do it yourself for around 10-40 dollars and save some money!
This job should take you, being a first timer, anywhere from 15-30 minutes. You don't need to be strong or mechanically inclined, you just need to be able to use a ratchet and the rest is like screwing in a light bulb. So let's get started.
Tools For The Job
- Ratchet or Torque Wrench
- Spark Plug Socket
- Socket Extension (8"-12")
- Anti-Seize (ask for a packet when you buy your plugs)
- 10mm Socket to Remove Vacuum Box
Allen Wrench to Remove Metal Plate Under Vacuum Box
Most of these tools are probably lying around your house and if not they can be bought for a few bucks at any auto or hardware store. A torque wrench is not required although I recommend purchasing one it you are going to be working on your car. At Harbor Freight tool store you can pick one up for ten dollars which is a good deal, plus once you have the tools you're always ready for repairs.
Spark Plugs and Coils for the 1.8 Turbo
I personally always use the NGK brand spark plugs which are easily available at Napa Auto Parts For around 10 dollars a set you can get the copper, or for around 35-40 dollars you can buy the iridium IX plugs. I would recommend the Following.
- NGK BKR6E (Copper) For stock cars, Stock #6962
- NGK BKR7E (Copper) For chipped cars, Stock #4644
- NGK BKR6EIX (Iridium) For stock cars, Stock #6418
- NGK BKR7EIX (Iridium) For chipped cars, Stock #2667
It's up for debate of when you you should change your plugs. From everything I've read on the topic the average response is about 40-60 thousand miles with iridium and about every 5 thousand with copper.
The choice between copper and iridium and which way you sway is up to you. They both have their pro's and con's. The copper have a cheap initial cost and are much better conductors of electricity. The iridium cost more at first, will last a lot longer, but they're not as good conductors. I found that my car idles smoother and runs better on the copper. So it just takes experimentation to find what works for you. If you like the way your car runs now, then just keep using that type of metal conductor.
For stock plugs (NGK BKR6E), gap them at .32 for chipped cars (NGK BKR7E) .28 seems to be the norm.
For coils I would just recommend buying the stock replacements from your local V-dub or Audi dealership. They cost around $35 each and it is always nice to have a spare in your car in case one burns out. Some people replace them from time to time but I don't see the point. Wait till one burns out grab your new one and stick it in in under two minutes. Why waste money on changing them before they go bad.
A little mod that a lot of people are recommending but I have yet to try is using newer MK5 and MK6 coils instead of the normal MK4 coils in our 1.8t's. They are longer and stick up about a fourth of an inch more (some companies like I.E. are making adapters) but they are said to deliver a smoother idle and higher performance. You will need to gap your plugs to around .40 if you choose to test them out. Once I get some I will update this post.
Open the Hood and Let's Get Started
- First remove your engine cover by turning all the plastic screws about a quarter turn and you should be able to lift it right off.
- That little flat looking can covering your last coil to the right is your vacuum box. It is held on by one 10mm bolt. Simply remove the bolt and move the box out of the way.
- The plate under the vacuum box has three 5mm allen head bolts. Remove the the bolts and take off that plate. Take care not to drop the bolts into the unknown.
- I would take a minute to have a beer and clean off any dirt and oil that has collected on your valve cover for two reasons. A) Makes it look nice, and B) A good precautionary measure to keep any dirt from falling into the cylinders.
- Go ahead and unplug all of the coils by pulling back the little tab on the harnesses. Sometimes a flathead screwdriver will help but take care not to break them. They do get brittle and break over time so if you do happen to break one don't worry your harness will still stay connected to your coil (DIY if you break the harness clip).
- Grab the front and back of the the coil and slowly pull up. When you hear that pop, (don't worry you didn't break it, they are just suctioned cupped in there) you can fully pull out the coil. Place the coil to the side and get your tools
- I like to tape the sparkplug socket to the extension with electrical tape because there is nothing worse than having the socket stick on the sparkplug when your taking them out or putting them in. Unscrew the spark plug and pull it out. I will include a link at the bottom of how too inspect it to see if it is running to cold or hot.
- Put a little anti-seize on your finger and rub it into the treads of your new plug. Stick the plug in your socket and screw it in only using the extension to avoid cross threading. I like to do a back turn first just to make sure the threads are properly aligned. Then with your torque wrench torque it between 15-18 ft/lbs. Push your coil back in, connect the harness and you are ready for the next.
- Put back on your plate, vacuum box, engine cover in the reverse of how you took them off and you are done.
- Smile and finish your beer because you just saved yourself at least $100.
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