Getting P0302 misfire code 97 A4
 

So a few weeks back I started getting a misfire code for cylinder 2 P0302. I moved around the coil packs and the code didn't follow the packs. I bought another just in case (never a bad thing to have an extra coil pack around with these cars). Checked the plugs and they looked normal. Replaced the coil pack with the new one...no change... so this narrowed it down to the ICM. Got a new one of these and replaced the old one which was replaced about 4-5 years ago. This stopped the problem (misfire code) for about a week. It began acting up again 2 days ago. Misfire #2 and would not accelerate. You'd be driving along and it would go limp...it would idle if you feathered the throttle but no acceleration and would only rev to about 2000 rpm. I pulled the plugs and they looked fouled compared to when I pulled them previously. The gap was large as well .045 on all plugs. The car has a 1 bar chip 91 octane. I replaced the plugs about an hour ago and drove to the shop to check on my other project (1989 Mustang 2.3 turbo notch). I fired it up and it started fine, idled fine, and drove to and from the shop fine. Do you think the previous misfires and large gaped plugs were the issue???

From what I've read the P0302 seems to indicate the ICM.
Oh and the new plugs are ngk double platinum gaped at .030
1997 audi a4 1.8tq 5 speed with 198000

Any thoughts....Replaced the coil pack, ICM, and plugs and it's still not running right. I think I'm gonna take it to a mechanic. What else do you think it could be???

The engine needs three things to fire: fuel, spark, and compression. We'll assume your compression is fine (though a quick test to get some baseline compression numbers is never a bad idea.)

You said you've swapped coil packs and the misfire didn't follow it. Good.

You've confirmed that the plugs are new and gapped correctly? A stage 1 tune on stock coils should be running a .028" gap.

If you've confirmed both of the above and you're still getting a misfire, swap fuel injector #2 with #1 (or #3, whichever floats your boat.) See if the misfire follows the injector.

If the misfire is still on cylinder #2 that leaves you with the ICM or bad wiring. You can try replacing the ICM, though you said you've already done that. Pull back the boot on the #2 coil pack connector, check for damage. Use a multimeter to confirm wire continuity between the coil pack connector and the ICM connection. Wouldn't hurt to check continuity from the ICM connection to ECU, but that takes a little more creativity. If you want to check that I will give you the proper pin numbers.

Finally, you could eliminate the pesky ICM altogether by swapping to the 2.0TSFI coil packs. This gives two benefits, the first is that the ICM is no longer a problem since it is eliminated, secondly it allows you to run a larger plug gap (0.040") with the hotter coils.

I considered doing the 2.0 coil swap to get the newer coils and eliminate the ICM. It's a bit pricey. I'm gonna drop it off at german master tech today or tomorrow. I'm sick of dealing with this thing. The issue is intermittent as well. I replaced the coil pack first and it worked good for about a day, then replaced the ICM worked for about 2 days, replaced the plugs and worked for about a day. It drives along fine and then barely runs (wont move while running). Shut if off/on until it finally kicks on and kicks out a nice cloud of black smoke. If it's not any of the above I'm thinking MAF, Injectors, or Throttle Body?
I replaced the MAF about 5 years ago, the coolant temp sensor was replaced with the green top on a few years back as well.