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    #1

    Weird hesitation issue

    specs:
    84 325e
    M50NV
    ZF320
    OEM brand new clutch
    2.93lsd

    Well, for a long time now i figured this was my parking brake sticking, but today i purposely left the parking brake off and left it in gear for the day. heres what happens:

    after sitting for the day(8am to 4pm) when i pull out of the parking lot it has a hesitation and it seems exactly like a brake is sticking. It doesn't do it every time, but it slowly seems to be happening more often. As i let it basically idle as i pull out of the parking lot it sounds like i have mild lumpy cams(only fluctuates maybe 100rpm), and when i tap on the gas it lurches forward, and when i let off the gas it lurches back a bit. As i pull onto the road and accelerate, at around 2k rpm is hesitates a bit, and then like releasing the brake it breaks out of the hesitation and accelerates quickly. This only happens for maybe the first 1/2 mile of the drive. After that i can drive all day long, from complete stops, etc and everything is smooth. I can even park at the store, run in and grab a few things, and come out and its still fine.

    I am stumped as to what it could be, it seems exactly like a brake is grabbing, hence why i figured thats all it was, but now with this last time i am puzzled.

    Any ideas?
    Last edited by MattM; 04-30-2010, 10:19 PM.


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    #2
    You getting any codes? Is your throttle plate closing all the way?

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      #3
      no codes, when i do stomp test i only get 1444.

      as far as i can tell the plate is closing all the way.
      Last edited by MattM; 05-01-2010, 11:09 AM.


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        #4
        im thinking it may be one of the caliper pistons now...


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          #5
          Sounds like a faulty HFM to me. Try swapping with a known good one for good measure.

          SINdelle:E36 M3 5-Lug | 17x8 & 17x9 BBS RS | S52/ZF | 2.93LSD/3.5HFM/24lb Injectors/C&S Chip[B]SOLD[B]

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            #6
            hmm, i tried unplugging it and running the car, the idle bumped up a bit, and i got the check engine light coming on. also, if it was the HFM you would think it would be a constant problem, not only for the first few minutes of the drive.


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              #7
              Weird. Does seem like a sticky caliper. You can always jack the car up and turn the wheels and see if one of them is locked or at least grabbing. Sounds like it would be the rear brakes unless you notice something odd in the steering when you first drive it. idk?
              You're entitled to your own opinions, not your own facts.

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                #8
                I'd try cleaning the HFM first. Takes 20 min, and fixed 90% of my lumpy idle. I get the accel/decel lurch too, but only happened once since I cleaned it. Haven't been able to reproduce it since though. Clean the HFM and ICV and see where you are from there.

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                  #9
                  my 88 325i with the m20b25 still in it[:(] does this exact thing.
                  check engine light is on but stomp test doesn't work(I think my WOT switch in the TPS is dead?)
                  sigpic
                  Originally posted by e30hijinks
                  I move faster than "the speed of light." I'm always connected to my Blackberry and am ready to purchase at a moment's notice. I do not play games

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                    #10
                    ICV was cleaned 3000km ago when i did the swap. how do you recommend cleaning the HFM?

                    It seems hard to believe something could be wrong with the engine, because it doesn't happen every time, and when it does it goes away within the first few min.

                    I tried jacking up the car after it has been sitting overnight, and couldn't find any 'sticky' wheels.... I think i may try going out and getting the brakes nice and hot again like you do when you set brand new pads. and then see what happens. Ill also try cleaning the HFM


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                      #11
                      Undo negative terminal on your battery. Unplug the wire from the MAF. Undo the two security screws on either side of the MAF with pliers or vice grips. They are not on very tight. Take something very thin like a knife and pry the edge of the rubber up around the screw holes just enough to separate the MAF from the tube housing. Pull the sensor out carefully, and spray it good from a foot or so away with CRC Mass Air Flow cleaner (autozone). Get it all over the sensor, in and around it. I let it dry in an open zip lock bag for a couple hours and put it back in. Remember not to get your finger grease on the electrical stuff. I used rubber gloves.

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                        #12
                        well just don't hesitate anymore make a decision !

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                          #13
                          well, i cleaned the maf this morning, noticed an immediate change in starting. and it seems the throttle response is better now aswell, i didnt have the hesitation in my quick test drive, so maybe thats what it was... im going to just monitor it over the next few days and see


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