99 audi a4 misfire issue! help~!!!
 

hello all, every time i start my car it dosnt want to idle it starts just fine then a second later it dies. i start it up again give and rev it up a little then it goes down to 400 revs and then slowly idles fine. after that i drive it around and then it misfires. i always had cylinder 1 misfire, but after i replaced its coil it is now cylinder 4 that misfires. it always seems to misfire after the car warms up. also when i checked it out it seems that my cars temp when its warm is 150F. i ordered a new ICM but anything else it could be, im thinking fuel pump.

Have you verified that the plugs are good and are gapped right? .032" stock and .028" chipped.

no i have not, ill let you know what they are.

i checked them all and they are at the correct value. i just replaced the ICM and tested it yet still cylinder 4 continues to misfire. i tested the fuel pump, that too is fine i just cant figure it out!

i just noticed that there is no heat sheild next to the exhaust manifold, could that be the problem?

I suppose it could be putting some additional heat on the head but I doubt it's enough to cause it directly. BUT - if the missing hear shield allowed excess heat to damaged the cool harness for that cylinder, that'd cause your problems. You may also have an injector problem. You can swap the #4 injector with one from another cylinder (have new injector o-rings on hand - reusing them can cause a leak and a fire). Have you swapped the #4 coil pack with one from another cylinder? They can die at any time.

i have not done any of those, ill do that and let you know

Definitely start by just moving the coil packs around and see if the misfire follows the coil pack. I'm fairly certain its just another dead coil pack.

When one dies the others usually aren't too far behind and its a good idea to just replace all 4 at the same time; if you have the money.

The heat shield should have nothing to do with it, and if replacing the coil pack fixed your cylinder #1 misfire, it seems unlikely that #4 would be due to bad injectors or some other cause.

I think i may have solved the problem, i swapped the coils and injectors. Drove it around for a bit and no misfire!

Strange. But if it works it works! The free fix is always a nice surprise to come across. ;)

Could've just been a connection issue that worked itself out. Cross your fingers it doesn't rear its head again soon though.