jagyeman

Hey guys i need help my check engine light is on and when i tookl to autozone i was told i had a missfire thats what came up on the codes .how do i check to see which coil is bad help please .

PAREDLINE

It should say which cylinder is misfiring. The only exception is if the code is "random cylinder misfire" which means you probably need new spark plugs. How did you get to start a thread without 15 posts?

nfafan

Ask Autozone about a SECOND ECU code. If scanner shows a second code of:

P0306 (0603) = #6 Cyl misfire
P0305 (0604) #5 Cyl misfire
P0304 (0605) #4 Cyl "
P0303 (0606) #3 Cyl "
P0302 (0607) #2 Cyl "
P0301 (0608) #1 Cyl "

If second code shows a P0302 for instance, then try swapping Cyl 2 coil with Cyl 4 coil and see if code now throws a P0304.
If prob follows the coil to the new position - you confirmed your one bad coil.

Instead of swapping positions, could also try just disconnecting the suspected bad coil wire from coil - if engine roughness seems unchanged, you have the bad coil.

If no Autozone "second code" - you might have to do this disconnect trick for EACH coil. When you disconnect the one where no apparent diff in roughness occurs, you have your bad coil. Time consuming, but works.

Also, if just the P0300 (0701) Multiple cyls misfire code, the book sez;

Improper spark plug
Insufficient compression
Incorrect fuel pressure
EGR valve
The injector circuit is open or shorted.
Injectors
Intake air leaks
The ignition secondary circuit is open or shorted.
Lack of fuel (injector issue???)
Magnetized signal plate (flywheel or drive plate)
Front heated oxygen sensors

HTH
Steve