Announcement

Collapse
No announcement yet.

M42 running rough, hesitating, 1222 code

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    M42 running rough, hesitating, 1222 code

    Hi guys

    Just trying to get some ideas about a problem I'm experiencing. Just bought a '91 318is and have been experiencing the following problems:

    1. Start up is hard, whether hot or cold. Gotta give it some gas to keep it running, but even then it usually takes one or two tries to keep it running. After you initially "catch" it it will start to idle decently on its own.

    2. When accelerating, if you give it part throttle it will accelerate fairly smoothly up to around 3 or 4k rpms, at which point I have to play with feathering the throttle to keep it accelerating because it throws the CEL and bogs. At any point if I go WOT, it throws a CEL and bogs down.

    3. On the highway when driving at a steady pace, say 70mph or so in 5th, if I go uphill and attempt to keep the same pace, or try to accelerate on flat ground (i.e. put a load on the engine) it throws a CEL and bogs down. The CEL will usually stay on until I take the load back off the engine (either by going downhill or letting of the throttle), but often the CEL and reduced performance will stay on until I slow down significantly and then downshift.

    The code it is giving me is 1222, or bad fuel/air mix. One of the things that strikes me as odd is the way the CEL is directly connected to poor performance. I.E. the second the CEL comes on I barely have power. The second it goes off power comes back. Its like a crazy light switch.

    My searches have suggested fuel delivery issues but I'm skeptical bc the car got a new fuel pump in 2012. It also doesn't seem like a vacuum leak issue the way the problem is so off and on. To my mind a vacuum leak would affect it in similar fashion at all times. For clarity, the motor has about 145k miles on it and is all stock except for a HQ Autosport COP conversion. Anybody have any ideas about what might be causing my M42 to run so poorly? Thanks!
    Last edited by ChaseN; 04-22-2013, 10:06 PM.
    1991 318iS
    1992 911
    2006 330i 6-Spd ZSP people hauler

    Gone:
    1989 M3 S50B32, 6-Spd
    1990 325ix 5-Spd


    #2
    Was it running good before the COP? Check fuel pressure?

    Comment


      #3
      I bought it with the COP kit installed. I will try and hook a gauge inline and test it this weekend. Any tips for a good place to splice in the gauge?
      1991 318iS
      1992 911
      2006 330i 6-Spd ZSP people hauler

      Gone:
      1989 M3 S50B32, 6-Spd
      1990 325ix 5-Spd

      Comment


        #4
        Maybe the Afm?

        -NICK

        Comment

        Working...
        X