1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

PCV Problem?

Discussion in 'Audi S4/A4/A4 Cab (B7 Chassis)' started by viceroy, Aug 1, 2012.

  1. viceroy
    Offline

    viceroy Member

    Joined:
    Aug 17, 2011
    Messages:
    215
    Likes Received:
    16
    Bit of history first.

    I had my car serviced about 1800mi ago (2 months) and and at that service they replaced the PCV.
    About 2 weeks after that service, I started noticing a slight intermittant flat spot at 2000rpm. I don't know if flat spot is the correct term for this, but basically if I had lifted off for a few seconds then reapplied throttle, nothing would happen for about 1/2 a second then the car would suddenly come alive and I could accelerate again. Have been suspecting it was the multitronic, but I took it back to Audi and they keep telling me there is nothing wrong with the car, even after I showed them the flat spot. (It seems their attitude is if there is no error from the computer, there is nothing wrong)

    This morning when I got to work, I put my car into Park and noticed that the revs rose to about 1100-1200rpm and sort of hovered around there.

    I revved to 2000rpm, the revs would drop back down to 800rpm for a second or two and then rose back ro 1100rpm.

    I revved to 2000rpm again and the revs dropped to 800rpm, but idle was very lumpy...the whole car was shaking slightly, then the idle became smooth, and then after a second or so, the revs were hovering between 1100 and 1200rpm.

    Didn't do this when I was leaving home and the engine was cold.

    I'll go do a VCDS scan during lunch to see what errors pop up.

    I suspect the idle issue is PCV, but could it also be creating a flat spot at 2000rpm?
    Maybe the car is just trying to tell me to get a younger model...perhaps something with an 'S' in the name ;)
    #1
  2. bowen
    Offline

    bowen Member

    Joined:
    Mar 28, 2011
    Messages:
    457
    Likes Received:
    14
    Start the car and try to remove the oil filler cap. Is there suction? If so then its PCV fault. (at least thats how it works on the b6)
    #2
  3. viceroy
    Offline

    viceroy Member

    Joined:
    Aug 17, 2011
    Messages:
    215
    Likes Received:
    16
    Definately suction, and idle definately gets worse.
    Scan only showed up one code - P0507
    #3

Share This Page