weird idle problem
 

I have a rough idle in my 02 a4 1.8 tip quattro with 86k. At idle it sounds like it has a really bad miss, but if you rev it higher like at 2 or 3k it runs fine. I know that the plugs need to be replaced so im going to start there, then im going to drive it about a mile to autozone to check the codes. It does have a solid CEL. Is it safe to drive it like that to autozone? Does anyone have an idea what the problem might be? Thanks

RE: weird idle problem
 

possible vacuum leak or coilpack.

RE: weird idle problem
 

odds are its a coilpack. but check all your breather valves also they tend to corriode quick.

RE: weird idle problem
 

Check for the codes

RE: weird idle problem
 

ok the only code was for a cylinder 4 misfire. i got the plugs, the ngk iridiums because they couldnt find the right bosch ones in the system. everywhere in town has to order the coil. which is better, duralast or borg warner? thanks guys

RE: weird idle problem
 

ok swapped the #4 coilpack and all of the plugs and cleared the code and the car is fine. couple of weird things i found while doing it though... every plug was covered in oil. it wasnt the ends where the spark happens but on the thread and down in the shaft. only the dealer has changed the plugs and the head gasket was replaced earlier this year. also, the car does not use much oil, maybe a quart every 10k which the dealer said was normal or better than normal. second weird thing is one of the coilpacks was different than the others. im assuming it is the one the dealer replaced a few months ago. it is red on top and has a slightly different part number than the others.


p.s. doing these plugs makes me happy i didnt give the dealer the 150 or 200 they wanted to swap them! it took about 20 mins.


edit: fyi i hadnt thought before today to check with the vw dealer for the coilpack so i did and they were able to cross it with my vin and find the right part, and they had it in stock.

RE: weird idle problem
 

Pretty sure spark plugs aren't supposed to be covered in oil (perhaps someone can confirm this). You could have another leak. On the ignitors, they are called coilpacks and there are different versions of them out there.

RE: weird idle problem
 

the only thing i can think of is maybe they put the oil in there as anti-seize