So I have been messing around with this car for the past 3 months it started off with a misfire in cylinders 1 and 5 which are on opposite sides of the engine.

I talked with my mechanic (this is the first Audi he has worked on) and he suggested it might be the coil if its the random misfire. So I went ahead and purchased the coil pack but did not install it. We checked with alldata and mitchell, as to what the resistance should be, the resistance that the new one was giving us against the old one the new one had a lower resistance than the new one and when it did misfire it did not feel like one where it shakes and shudders.

So we moved on and replaced the fuel filter, changed gas companies (according to what mitchell and alldata said), spark plug wires are new, spark plugs new, and speed sensor.

With the speed sensor we replaced it and it stopped doing it but after the car warmed up and was tuned off it would not turn back on so we put the old one back in and is working like before and turns on. Just today we replaced the fuel pressure regulator and we found out that the old one was broken(the filter inside was broken) but now its doing the misfire after slowing down coming down from 40 or 80MPH it will do the P0300 along with P0301, P0302, P0303.

We have been using an INNOVA 3160 Scanner which is suppose to help with the solutions on their database but it is not helping. I can post what INNOVA's website says if you guys would like.

Any other info that you guys may want to know just say so.

Really home someone might be able to help or suggest other things to look at.
Thanks

 

Possible issues:

Coolant temp sensor
Improper plug gap (should be .032" - did you verify they all are gapped right?)
Primary O2 sensor issues
Crap in the fuel filter, lines, or injectors
Any additional codes besides the misfires?

Any feedback on this stuff may help narrow things down. And definitely post the scan data - every bit of info helps.

 

Thanks for the reply.

Coolant temperature is the one that goes under the reservoir right? I plugged it in all the way and recently (3 weeks ago) replace the entire water and added the Audi coolant. The water had a brown look to it and would leave white residue if it splashed on other parts of the car.
The spark plugs the car had before where the VW/Audi OEM with a double tip. So I got the double tipped ones that don't need to be gapped. Or am I wrong?
I had seen an o2 sensor code before but I thought I had to do with the cat. I did get a P0902 code which was air intake bank 2 but have only gotten it once or twice at different times. I think it was to do with the intake clams not been screwed in all the way.
The fuel filter was replaced. It was still the original one from Audi and dated back to 2001. The gas that was in the filter was dark. So it might be that crap is in the lines or injectors. I try to check that later this week.
As for other codes its only been P030X,P0902, and others for the intake when I did not secure it all.

One of the vacuum lines that goes to the pressure regulator was pinched so we changed to a different hose.
I'll post what the scanner codes say later today

Thanks

 

Here is what the INNOVA OBDII Scanner said. I was wondering if VAG-COM might be able to give me more specific info regarding what is wrong or would it pretty much just give me the same codes of misfire?

Ill be cleaning the fuel lines tomorrow and checking the injectors.

 

I got the triple electrode plugs for my B5, and they were supposedly pre-gapped correctly and should not have needed adjustment. But when I checked them, they were all different/wrong. So I adjusted them to .032 and they worked wonderfully.

 

Ill have to check the gaping between them.

So yesterday we took it for a long drive after changing the Crankshaft speed sensor and adding a Lucas Deep Clean Fuel System bottle. It was about 40miles on the way out it jumped from being a multiple misfire at cylinders 1,2,3 to those being ok and having a misfire in the 2nd bank cylinders 4,5,6 and later maybe 10miles out it changed to cylinders 4,5. So we cleared them and the rest of the trip there was code free.
On our way back the misfire came back to cylinders 2,3 after I accelerated up to 4500 RPM from a stop light. after that back on the freeway it did not give me another codes.

We were talking about this with another mechanic and he suggested getting the ECU checked out to see if there might be something wrong with it. His reasoning was that if it was a misfire that had to do with the coils, Spark plugs, spark plug wires, injectors or fuel line it would be doing it in the same cylinder. Since that was not case and the misfire has been jumping around from cylinder to cylinder it might just be a fault in the ECU.
What do you guys think about it? and where could I get it checked out?

Thanks

 

Anyone have Any suggestions?

 

try checking the ignition control module? might be silly but worth a shot.. after replacing all the coil packs and sparkplugs i still had misfire. not until icm was replaced that everything went back to normal..

 

So I replace the ignition coil. The old coil has the plastic all soft. So it was replaced and it still is giving me the misfire in 4,5,6.
I'm getting tierd of this car at this point. Anyother things I can check?