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New coil, same old problems...Fixed!

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by angrysnowplow, Apr 15, 2003.

  1. angrysnowplow

    angrysnowplow 1/2 ton status

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    This is on my '90 TBI 350. Ignition module was replaced because it had the same symptoms as last time. Made no difference. It wasn't getting any spark, I tested the coil w/ an ohmmeter, it was bad. With the new coil, it fired right up, but soon started with the same stuff as before. Runs crazy rich (blows black), dies with any decent amount of throttle (especially from a standstill) and then doesn't want to start back up. I'm at my wit's end here, any ideas? /forums/images/graemlins/1zhelp.gif

    *Turns out it was the map sensor, runs great now. Thanks everybody for helping /forums/images/graemlins/thumb.gif
     
  2. bee32

    bee32 1/2 ton status

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    Re: New coil, same old problems

    Didja check yer timing??? Just a thaught.
     
  3. ratchetmaster

    ratchetmaster Registered Member

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    Re: New coil, same old problems

    Does the 90 have a throttle position sensor??
    if so, could be the problem. Or a bad O2 sensor . . . thinks it needs more fuel but doesn't so it is running it rich.
     
  4. 90K5

    90K5 1/2 ton status

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    Re: New coil, same old problems

    vacuum leak maybe? spray carb cleaner around the gaskets and see what happens
     
  5. angrysnowplow

    angrysnowplow 1/2 ton status

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    Re: New coil, same old problems

    I forgot to mention that all those gaskets are new- I had the heads off a little while ago...but do you think a vacuum leak could be so bad as to keep it from starting?
     
  6. angrysnowplow

    angrysnowplow 1/2 ton status

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    Re: New coil, same old problems

    I believe it does have the throttle position sensor..
    A mechanic recommended trying to start it with my foot to the floor- says it will make the computer recognize that it's flooding and stop fueling it... didn't help. I still think it's an electrical thing tho... don't mind me, just thinking out loud. /forums/images/graemlins/ignore.gif
    The O2 sensor is a suspect at this point- the wire ended up getting cut while removing the manifolds (hey, what are friends for /forums/images/graemlins/tongue.gif)I put it back together with a crimp connector.
    Thanks for everyone's input so far. /forums/images/graemlins/thumb.gif
     
  7. RockyRider13

    RockyRider13 1/2 ton status

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    Re: New coil, same old problems

    I believe that it is either the thirdgen.com or some other f-body website that has the TPS adjusting procedure. The computer could be thinking that you are giving it some pedal when you aren't. I would rule out the 02 sensor because it doesn't give the computer input until the car is warm (closed loop). When it runs, does it throw any codes?
     
  8. k5blazerus

    k5blazerus 1/2 ton status

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    Re: New coil, same old problems

    Just a thought. did you check your MAF sensor. That will cause it to run rich.
    Colin
     
  9. angrysnowplow

    angrysnowplow 1/2 ton status

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    Re: New coil, same old problems

    mass airflow sensor? I'm not even sure if I have one of those /forums/images/graemlins/eek.gif Hafta consult the Chilton book.
     
  10. angrysnowplow

    angrysnowplow 1/2 ton status

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    Re: New coil, same old problems

    Cool, I'll check out that thirdgen site for fuel injection stuff. Check engine light's been on, still trying to figure out how to read codes with a paper clip.
     
  11. alec78

    alec78 1/2 ton status

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    Re: New coil, same old problems

    I might be missing something but here's a couple of thoughts:

    1) If it is over fueling and won't restart, could the plugs be fuel fouled?

    2) Is the SES light on? If so, did you get the codes?
     
  12. 90K5

    90K5 1/2 ton status

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    Re: New coil, same old problems

    there is also a pickup coil in the distributor that goes out pretty often...wouldnt be surprised if thats the problem.
     
  13. RockyRider13

    RockyRider13 1/2 ton status

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    Re: New coil, same old problems

    Tbi engines do not have a MAF. The chiltons should have the procedure for pulling codes w/ a paper clip. If not, get the "scnner" from auto zone, well worth the $25. Find out the codes, that will give you a better idea of what the computer is "thinking" before blindly throwing parts at it.
     
  14. angrysnowplow

    angrysnowplow 1/2 ton status

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    Re: New coil, same old problems

    I'll look into those things, too. /forums/images/graemlins/thumb.gif
     
  15. k20

    k20 3/4 ton status

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    Re: New coil, same old problems

    bad temperature sensor in the manifold? Mine went bad tellin it the engine was hot so it gave it no gas, urs might be broken and stuck to cold, floodin it out.....
     
  16. angrysnowplow

    angrysnowplow 1/2 ton status

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    Bump /forums/images/graemlins/k5.gif /forums/images/graemlins/smile.gif
     

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