94 mtx hesitation/lugging/cutting out below 4k

Discussion in 'Gen 1 & 2 - Engine, Exhaust, Drive Line & AC syste' started by green94mtx, Mar 23, 2012.

  1. green94mtx

    green94mtx SHO Member

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    I did a search and couldn't find much, When i'm accelerating, it cuts out/lugs/hesitates mostly from 2500-3500 rpm. WHat could this be? Doesn't matter if i'm 1/2 throttle or WOT. Doesn't seem to happen below 1/2 throttle though (light acceleration). New crank sensor, new plugs, new intake & TB gaskets. Tried another used MAF and that didn't do anything, i cleaned it very throughly too. Any info would be greatly appreciated. Thanks
     
  2. rubydist

    rubydist SHO Member

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    pull the codes first.

    my guess is that the tps is bad, but you need to pull the codes rather than guess.
     
  3. green94mtx

    green94mtx SHO Member

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    Will do. I will let you know what i find. No CE light, but it's worth a try!
     
  4. itwonder

    itwonder SHO Member

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    KOEO and KOER tests. Pull codes.
     
  5. Vnuk1

    Vnuk1 Mr. Mayhem Staff Member

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    Just because there is no CEL, doesn't mean there aren't any codes...
     
  6. green94mtx

    green94mtx SHO Member

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    THat's why i said it's worth a try lol
     
  7. green94mtx

    green94mtx SHO Member

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    These are the 2 codes
    122 Throttle Position Circuit lower than minimum volt.
    157 Mass Air Flow Circuit lower than minimum volt.
     
  8. Vnuk1

    Vnuk1 Mr. Mayhem Staff Member

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    Unplug your MAF and drive it with it unplugged.
     
  9. green94mtx

    green94mtx SHO Member

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    What good will that do me?
     
  10. Vnuk1

    Vnuk1 Mr. Mayhem Staff Member

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    Don't ask questions, just do it.
     
  11. green94mtx

    green94mtx SHO Member

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    I unplugged the MAF before starting the car. CEL immediately came on. Started driving and it ran how it was supposed to! I was able to go 30mph in 3rd and give it roughly 3/4 throttle and it accelerated with no cutting out at all! Then drove another mile or so and it started doing it again....... ugh ******* SHOs
     
  12. Vnuk1

    Vnuk1 Mr. Mayhem Staff Member

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    When you replaced the MAF with another are you sure of its being a known working sensor? Do you have a known working TPS to swap in?
     
    Last edited: Mar 23, 2012
  13. green94mtx

    green94mtx SHO Member

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    Well i bought it at a junkyard for $15... So, i'm not sure on that one. And i do not..
    They're not too expensive. Should i try metering the voltage?
     
  14. rubydist

    rubydist SHO Member

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    ok, so either the tps is bad, or the ground to the circuit is bad - the tps and the mafs share the same circuit, and since both are being reported as bad it suggests a ground or power issue.

    trace the wiring and make sure all connections are good, especially the ground. if that doesn't do any good, then replace the tps, reset the codes, and try again.
     
  15. Vnuk1

    Vnuk1 Mr. Mayhem Staff Member

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    Do what he said and check your wires first, maybe you have a fubared wire or ground.
     
  16. green94mtx

    green94mtx SHO Member

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    THanks guys. I'll keep you updated
     
  17. green94mtx

    green94mtx SHO Member

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    Bought a new TPS just to see, and it didn't change anything. And i unplugged the MAF and it didn't change anything. Must've been a coincidence the other day. Where can i find the ground for that circuit?
     
  18. green94mtx

    green94mtx SHO Member

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    Where can i find the ground for that circuit? Still driving the car this way..........
     
  19. green94mtx

    green94mtx SHO Member

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    Update on SHO issues. The new TPS got rid of the 122 code. The 157 MAF code is still there. And now i have a new code 214. And still dealing with the severe bucking under acceleration. Unplugging the MAF doesnt do anything. But now that 214 Code bring me to think Cam Sensor? Crank sensor was done last year along with aux wire from DIS to negative terminal. Any info would be greatly appreciated. Thanks guys.

    I have a spare DIS i might try since its easy. Also, i heard i can unplug cam sensor and drive it that way just without a tach (and may take several times to start) thoughts?
     
  20. msteiny

    msteiny SHO Member

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    Hows your fuel pressure?

    Check to see how well your DIS is grounded and try re-gooping the back with di-electric compound also making sure the connectors are making contact.
     

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