HELP! Weird misfire!

[wangandreams]

The weird thing is that the car only misfires when I start it after the engine is hot. When I start it cool it runs smooth and gives me no trouble at all.

I've driven it for extended trips and when it starts normally-it keeps running normally. However if I shut it down and restart the 2nd cylinder starts misfiring.

I have swapped the spark plugs and cables and I'm pretty sure I have isolated the problem to the fuel system.

Any ideas?

Thanks guys, in advance!

 

[rush2252]

Have you used di electric grease on BOTH ends of the plug wires? Those bastard coils on the 420s do NOT like aftermarket plug boots. You have to push them rather hard to make sure they are tite.

If youve done this and are guessing fuel system trying using a steth or a long handled screwdriver to listen to the injectors. Compare the ticks if one is making a dull thud it could be dirty or going bad. Make sure you put the screwdriver in the same relative location on each injector as not to distort sound reading
A clean injector wil make a nice tick tick tick.

If your using a screwdriver use a longer one. Put the metal end on the injector body and stick your ear to the handle while its running. Works well for finding bad wheel bearings cam bearings etc


-Good Luck
Kolby

 

[habitatguy187]

Coil packs have been known to show signs of failure only when hot.