I have a 2005 A4 quattro with the 1.8L. It just turned 76k on the odometer. Yesterday I drove to work no issues parked and the idle sat high then the CEL came on solid. I left work and when I started the car the idle was still high and CEL was still on. Stopped to pick my kid up and plugged in obd2 reader. It came up with random misfire, misfire cylinders 1-4, and high idle speed. I cleared the codes and the idle dropped became extremely rough with very noticeable misses. I drove home a couple of miles and at higher rpms it smoothed out. I got on it once and it spooled up but not as peppy as before. When I got home I could smell oil. Popped the hood and the dipstick had been blown out and the engine bay was covered in vast amounts of oil. Not sure where to go from here. Could the pcv valve do all of this? A coil pack should not creat crank case pressure. I'm not rich enough at this point to take it to Audi or to start just throwing money at it. Any input is appreciated. I did flush out and clean pcv valve when the dealer said they'd have to order one and there was no change and all the same codes.

 

I had a similar problem just last week, with random misfires etc...bad idle, however, when i pull the dipstick, it got sucked back in...

replaced the pcv valve ($10 at my local VW dealer)...and all's well in the world again.

however, it seems you're getting positive pressure in the crankcase....so it might be that your pcv is clogged....a seafoam might help

 

Which pcv valve did you replace? $10 from the dealer?

 

There are three different styles for the car i have...03 a4 1.8t quattro

i called audi with my vin and they got me the right part number

but the valve i'm referring to is something like this:

Audi B6 A4 Quattro 1.8T > Search > Pcv > ES#5957 Pressure Control Valve (PCV) 19mm - 035103245A


DIY:
Crankcase Breather Valve Location

 

Ok that's the one I'm working on getting out. It's a whole different unit in my car. Stupid C-clip is being overly difficult with intake in place.