My 2004 Jeep Liberty Limited V6 is misfiring only within cylinder 6. We replaced the spark plug and ignition coil connected to it and the mechanic said that it doesn’t look to be the wires at first glance. The previous owner (I bought it a day and a half ago and then it misfired and stalled backing out of a parking space) said that it had a vacuum hose issue somewhere. There is also a code for oil pressure low. What do you suggest I do next? Compression/pressure test? Or check distributor?
Usually, ignition and fuel system related issues are the source of misfires. have the fuel injector for that cylinder checked. A vacuum leak can also lead to this problem. It's hard to tell whether the low oil pressure and misfire are related. Unless the cylinder is leaking oil and fouling the spark plug, leading to the misfire. If a bad head gasket is leaking oil into the cylinder this might be the cause. They need to find out whether there's actually low pressure.
Updated on September 29, 2019
By Dan Ferrell