Before we begin, I want to say hi to everyone on the A4 owners club. I just got mine and I like it quite a bit.

Background:
I'm quite a competant mechanic, I own a 99 corvette with about 500 whp that I have been daily driving for 3 years now. I do all my own work on that which is where my knowledge about cars in general comes from. I appreciate any help or suggestions you might have.

Now, onto the problem.

My 2001 2.8L v6 will bump occasionally at idle and will also hesitate during accelleration. Then one afternoon going uphill at part throttle it started randomly misfiring a lot, causing the CEL to begin flashing. After it stopped, the CEL turned off. From experience when this happens, the first thing I do is seafoam. Went ahead and did that. Got a decent amount of smoke, but nothing , and I have seen lots of before. Problem was still present so I run by autozone to pull codes. P0102 comes up as low MAF reading. From experience, I know to clean it, so I remove and clean the MAF and disconnect battery for 30 minutes. Restart and let idle for 5 minutes, problem is still present. So I really get down to the nitty gritty and begin going over EVERYTHING with a fine tooth comb. Then I found what I believe is the culprit.

The MAF connector on the harness side has 4 wires going into it. The MAF itself has 4 prongs. On the harness side of the connection there is an extra wire, a black wire, that looks like it should go into the connector, but has been cut near where the wires go into the sleave leading down into the rest of the harness. It is definately part of this set of wires. This wire sure seems like it would go into the MAF connector somewhere. I looked at the MAF where the connection is and in addition to the 4 prongs I see a tiny hole on the left side. There is no corresponding piece on the harness side of the connector.

At this point, the black wire is my guess(probably a ground). Otherwise it's gotta be an air filter (which I'm replacing anyway) as a part I don't mind throwing at the problem since I just got it.

The only other thing that could go wrong would be complete MAF failure. Symptoms do not indicate that to me.

Would one of y'all mind taking some pics of the MAF connector as well as your MAFs for me. The little black wire is part of the group of other wires. Most are green/some other color.

Anyone know where the black wire goes?

 

I don't have access to the wiring diagrams anymore, but in audi diagrams brown is always ground. Black is usually signal ground, meaning it would most likely go to the ECM, but i can't be sure of that.
Have you tried taking off the MAF connector and see if it runs any better?

 

The MAF code did not come back on, but it was still missing at idle and during accelleration. Came back with a code 302 and the CEL is blinking quite often now. Decided to swap plug in the cylinder, no luck. I unplugged the MAF and the idle bounced around for a while. When I tried to drive it on the street the car would die when I slowed down to stop at a light.

Went to look at the spark plug wire and when I tried to disconnect it from the coil it broke off flush in there. Fast forward an hour of me digging brittle pieces out with tiny screwdriver. I remove the coil pack and notice the two wires going into the coil are showing copper. I electrical tape them to my satisfaction and rip the elbow off the spark plug wire and attach it directly to the coil. (ghetto? yes) Reset computer and take her for a drive. Car drives excellent for a little while, but as soon as it gets to operating temp the misfire (code 302 again) starts happening during accelleration. At idle the car seems a little better.

So this morning I get in and car is driving fine while she's cold. As soon as it gets to operating temp though problem occurs and I can hear it popping and sputtering and the hesitation is substantial. From working on gm cars I'd guess that it's having a problem going into closed loop or something. Anyway, any suggestions on where to look are appreciated. I'm working on getting a spark plug wire to replace the broken one and possibly a used coil.

 

youre description of the car working fine until its at running temp sounds textbook for a bad coilpack... that is exactly how my car acted when this happened to me a few times. As far as the Maf threshold code, maybe it threw that because of the misfire who knows... i have a couple extra coilpacks in my garage that i bought as a precaution if you want them, but its probably easier just to go to ecstuning.com and grab one from them. Try putting the coilpack from the misfiring cylinder on a different cylinder, drive it and pull the codes, if the misfire has moved to that one, then you have your fix. hope that helps

 

I can confirm the MAF code was legit. It was dirty as hell. Now that it's clean no more code from that.

Please PM me a price on a coil shipped to 78730. I don't need all 3 of them, but if you're not willing to seperate that's fine.

Great pic!