No announcement yet.

Slight Engine Problems... Any ideas/comments?

  • Filter
  • Time
  • Show
Clear All
new posts

  • Slight Engine Problems... Any ideas/comments?

    So today driving to get my custom exhaust put on the car... it had the following problems.

    a. it would feel like it was about to die... so I gave it a little gas to stop it. Why is it doing this? *It never did this before*

    b. on the way there and on the way back, as I put the pedal down (not all the way) it would give me this huge delay / jerk.

    So we stoped at the local dealer to pick up a cap/rotor/spark plugs... I hope they will solve this problem...

    Any other ideas? I was thinking maybe stuck throttle bodies? Anyway to test this out?


    -Michael Abrahams *confused*

  • #2
    Check the the fuel pressure, it may be low. Does this occurs when the engine is hot, if yes, check air intake/manifold and coolant temperature sensors.



    • #3
      Thanks but what exactly should I be checking on the intake/manifold and coolant temperature sensors? The coolant temp is running right in the middle during these jerks...

      It's not a jerk when your coolant level is almost on red and your car can't go about 4k.... I know that feeling.... and it's not that.

      Thanks for your help!


      • #4
        Lean mixture? Idle air control valve? or maybe your Air Flow Meter?

        You also could have lost a hose connecting to the intake making the mixture lean. The hose on the back of the plenum has a nasty way of comming loose.

        Just a couple of other thoughts. The IAC is adjustable with the proper tools, and the AFM can be tested with a known good borrowed part. AFM's can be checked by other means, but sometimes they have "dead" or worn spots in them that will give you similar problems. I had a nasty jerk off idle with my AFM, but went away with my Maxx Alpha N setup .


        • #5
          there are many things this could be. it just so happens that my car was doing the same thing until tonight! i could cruise along at low rpm and suddenly lose power and have to pump the throttle to correct it. under acceleration it would hesitate and surge. i though back to the other day when i was changing my air filter and smacked my barometric sensor. i didn't think anything of it. after that is when i noticed the problem so i opened the sensor to inspect it. i had to bend the needle further over on the circuit board as the circuit had been worn off in the original position, hence making real contact and it runs correctly now w/ a really smooth idle.


          • #6
            Inside the AFM body, there is a small resistor mounted in the AFM opening (before the vane positioned right at the opening center). This senses the air manifold temp., try to clean this with a carburetor spray, maybe it is mudge with dust or dirt. Also, clean the connector with electrical contact cleaner.

            Check out also, you may have a fouled/defective spark plug.



            • #7
              Thanks guys!

              I know for a fact it's not the AFM since I just replaced it with a new 2.5L AFM about a week ago....but I will check just in case...

              We are changing the spark plugs on Thursday or Friday... so hopefully that is the problem.

              I'll let you guys know..


              • #8
                Originally posted by Bavarian3

                I know for a fact it's not the AFM since I just replaced it with a new 2.5L AFM about a week ago....but I will check just in case...

                Be careful saying such things. Every time I say something like that I have to eat my foot . You may have a defective one on your hands.
                Let us know what you find.


                • #9

                  I would suggest that if possible, you reinstall your original afm. In many cases, when you change something and a problem crops up shortly after the changed item is the cause.
                  Hope it turns out to be easy
                  88M3 henna

                  97 540\6-Gone
                  2008 MINI Clubman S


                  • #10
                    I would keep it simple, Is there possibly water in the tank?
                    another problem could be the O2 sensor,maybe yhey unplugged it and forgot to reconnect it?


                    • #11
                      Originally posted by Bavarian3
                      I know for a fact it's not the AFM since I just replaced it with a new 2.5L AFM about a week ago....but I will check just in case...
                      I would not say that as it IS probably the AFM. You DO know that you CANNOT put the E3 AFM on a car that doesn't have an E3 chip or the Conforti D Mod chip right???? The 2.3 or base 2.5 chip cannot interpret the AFM data from the E3 AFM.

                      Change the AFM back to stock and solve your problem.


                      • #12
                        Yes I did know. I already had the TMS 2.5L custom chip installed when I put the AFM and injectors in... So I know it's not that problem...

                        *Note* The car ran like this with 2.3L injectors and AFM

                        The O2 sensor is not the problem either... it ran like this before the exhaust system.... New O2 sensors as well..

                        A friend of mine said it could be a vaccuum leak. So I'm going to have something checked out with that...

                        So on my list:

                        Spark Plugs
                        Vaccuum Leak
                        AFM Sensor

                        for all the help!
                        Last edited by Bavarian3; 08-12-2003, 11:47 AM.


                        • #13
                          if you haven't already bought the cap and rotor. buy the volvo versions and save a bundle ($20 instead of $120)

                          Karl Kraus --Education is a crutch with which the foolish attack the wise to prove that
                          they are not idiots.


                          • #14

                            Thanks for that tip. We already bought the cap/rotor from the dealer but we get a nice discount.

                            The car should be going in tomorrow to the mechanics. I'll keep you guys update as to what the problem is...


                            • #15

                              Half an inch crack in the rotor....
                              Car runs fine now. We are going to replace the fuel pump as well...

                              Thanks again for all the help!