About a week ago I got a p303 and p304 error codes. My car had a lot of hesitation and it seemed like it had an engine misfiring.
My mechanic switched the coils to see if the misfire changes from one cylinder to another. Everything seemed so much better for a couple of days, but then the hesitation came back... it's not as bad as before, though.
He had told me that if switching the coils doesn't affect, then it's probably the injectors. I believe that the injectors are somewhat expensive, am I right?
I do trust my mechanic, but I was wondering if you guys have any advise, I'll appreciate it!

P.S. As a note, I had a similar problem about 6 months ago: I replaced the spark plugs and cleaned the injectors and everything was fine until recently.

 

Well is the misfire back on the same cylinder, or did it move? You never said!

 

I'll check. I took it to read the codes again, but since a problem with the exhaust/muffler just popped up, they told me to go fix it as it could alter the results from the scanner. I'm going to fix it today, get the codes and I'll report!

 

If you have coil-related misfires, a code from somewhere else in the car won't change the misfire codes.

 

I had the same problem and my car ran so awful.
i ran it to give it enough time to heat up and then took the coil back off right away.
I found there was tons of moisture in them and dipped paper towels in there and soaked it out and wiped the plugs off.

And repeated a few times and now my car runs perfectly.

 

Sorry I took so long. I fixed the muffler and it took about two days for the engine light to come back on. Since then I've taken my car to the mechanic twice. He cleaned the coil and the plugs, but both times the problem has come back up. The last time he said that he had put a more "grease" in the sealing than it needed it. He said that you usually put a little bit of grease and with the engine's heat and the grease the rubber/seals will stay put.
The hesitation has become worse, I will take it once again, but are there any suggestions for me?

By the way, before the last time I went to the mechanic, I went to autoZone and got the codes, Now i had 3 missfires, I think they were p301, p302, p303.

I appreciate your help!

 

I had a similar problem last month with my 98 2.8qm. it was reading a misfire in cyl 4. after swaPPING COILS, PLUGS, AND MAF it turnrd out to be a pin hole in the injector o ring that seals it to the intake. It was a total pain in the *** to track down. Good luck.

 

I just took it back to the mechanic. I have p301/02/03 codes. He said that the plugs/coils couldn't have the same problem at the same time or the car wouldn't turn on. He also said that the coils/injectors/plugs had no oil on them. He said the the problem could be caused by two things, but none of them are good:
1 fuel pression problem
2 some electric problem (for which I would have to take it to a dealer!!!!)
They're running some tests on the fuel pressure, but he recommended to get a diagnostic from Audi before proceeding.

What do you guys think?

@ Mckayiva4 where your plugs filled with oil? How did you detect the problem?

 

There was some oil in there but not much. I did my valve covers last summer along with the spark plug seals. I started by replacing all the plugs, then moved the coils aoround(my friend had one i knew was good some we swapped them. after that i pulled the fuel rails and inspected each seal. It took forever. good luck

 

Update: it just passed the fuel test, it might have to do with the electronic system. I have to take it to the stealership to get a diagnostic and then my mechanic could fix it!