Hello everyone,
I recently purchased a 2006 b7 a4 quattro avant 2.0t and am trying to troubleshoot its problem. I have a flashing CEL when car is in motion, solid in idle.

Originally, I was getting misfire of cylinder 3 and 4/multiple misfire detected. I changed the coils, sparkplugs, and cleared the codes and now its just showing a misfire on cylinder 3. The car runs rough and there's some smoke coming from the exhaust. When I changed the sparks there was oil on them. There's actually quite a bit of oil on the bottom of the engine as well but I can't see it coming from anywhere in particular and the oil level has remained normal.

I've done my research but what I'm seeing in my car doesn't match up with most misfire's I read about. The loss of power when driving is pretty immense. The engine is very choppy and I can hear the turbo very clearly. (I had to move the car)

With the oil on the plugs, I'm now thinking I should change the valve gasket. I realize this probably won't help my misfire though. Does this sound like a bad fuel injector? Is it possible that the cam follower/cam is damaged? I would think it would generate it's own code in addition to the misfire but I'm not sure. Any advice would be highly appreciated. I'm currently in school in the Appalachians and there are no audi dealers within 50 miles. Thanks

 

Oil on the plugs could indicate the turbo has blown seal and oil is being sucked into the intake. See if there is oil in the ducting from the intercooler to the intake. If so, this will indicate that oil is being introduced into the system before the intake. Also another thing to check would be to the PVC valve. Crank the car and try to remove the oil filler cap on the valve cover. If you feel the cap being sucked back into the hole, the PVC is shot and allowing too much airflow through. This can suck oil spray from the valve train into the intake.

Where in the Appalachians are you going to school?

 

Thanks, I'll check the intake later today. I'm by myself so can I check the cap while the engine is running? Also, would these cause the misfire?
I'm in the Cumberland gap area. Thanks

 

I'm just north of you in Wise County.. Are you going to LMU? There is a shop in Kingsport that I recommend. Blue Ridge Motorsports on Fort Henry Drive.

Oil being sucked into the fuel/air mixture will cause a misfire. Oil doesn't light up as well as gas. Too much in the mix and it will foul the plugs.

 

Yeah, I'm in the vet school. It would over an hour and a half to get there, but thanks. If I can't figure it out I'll rent a trailer and pull it up there. And that makes sense, I'll do some diagnostics tonight.

 

Clean the spark plugs off with some solvent (Brake Clean or Throttle Body Cleaner) and let them dry. Put them in and see if it will fire up and run at least for little bit. If it does and after a few minutes starts to misfire and cough. Shut it down. Let it cool off and pull the plugs. If they are fouled with oil again, that is the problem. Oil is getting sucked into the intake somewhere. The PCV or Turbo would be my two first suspects. Start with the PCV valve. It is the cheaper and easier of the two to fix.

Oh, and if you run into Stan Kunigelis (Dr.K) down there, tell him Dave Cantrell from UVAWise (I'm not working there anymore) says, Hi..

 

I'm having a very similar problem with my 06 A3. I had a misfire in cylinder 4 and the car ran like crap, barely made it over 20 mph. I changed the #4 coil pack and it cleared the problem up immediately while the CEL took a few days to go away. Then about a week later I got a stumble on takeoff and a check engine light. Read the code and there was a misfire in #2 and #4, but afterward the car ran fine. So I bought another coil pack and the weather got crappy so I had to wait a few days to get to it. I drove the car gingerly in the meantime. On Thursday the CEL kicked off by itself! I did a ton more research and have narrowed it down to either turbo seals or the PCV. Im praying it's the PCV! I bought one online that should be here Monday. I'll update with what I find. Hopefully it will help!

 

Sounds good. I'm checking my PCV after I get the valve gasket replaced. Unfortunately there were 2 valve cover bolts with stripped heads so I have to wait to have new ones delivered. I'll keep you updated on my progress as well.

 

Ok, valve cover replaced. It was in horrible shape. Put everything back together, swapped the sparks and still getting a misfire on cylinder 3 and 4 with the multiple misfire code. Is it possible the burnt oil clogged the fuel injectors? The PCV seems to be fine. There wasn't any suction when pulling up the fill cap. I'm going to see if running some fuel injector cleaner does anything. Any suggestions or other ideas? Thanks

 

I don't think a little oil in the intake would affect the injectors. Is it running better though? You'll need to clear the codes on the ECU because they won't go away until you erase them. Running some injector cleaner would be a good idea though. I like Sea Foam myself.