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P0068 MAP/MAF - Throttle Position Correlation HELP!!

Discussion in 'Engine/Tuning' started by GodStang, Nov 15, 2005.

  1. GodStang

    GodStang Active Member Established Member

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    Help I got a check engine light. It is P0068. I looked it up and it says P0068 MAP/MAF - Throttle Position Correlation

    Does this sound right? What could the problem be? I am on my break up tune.
     
  2. FireRed04Vert

    FireRed04Vert New Member Established Member

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    I am surprised no one chimed in here for you. I'm not familiar with that code. But I'm wondering if it doesn't have something to do with the expected voltages from the TPS at a certain voltage from the MAF. In other words, there should be some sort of matching correlation between the two. You shouldn't have a MAF with a reading that would indicate WOT and a TPS sensor at only part throttle. Just a thought is all.
     
  3. GodStang

    GodStang Active Member Established Member

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    Thanks for the reply and I think you are 100 percent correct. Our TPS voltage was at 1.2 and we adjusted it to .99 so we will see if the code comes back.
     
  4. Blown38

    Blown38 Member Established Member

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    I know this is an old thread. I am getting the same code on my dad's marauder. The car has basically a cobra setup on it. 2.3 whipple on a 9.2 comp teksid, single blade accufab. It is untuned with the whipple, but was kicking the code on the tuned m112. I have resealed everything, tried a different MAF, TP voltage is at .93v now. The only thing I can think now is the tune needs to be tweeked. I also swapped what I think is the MAP sensor, but havn't driven the car yet to see if it fixed it. Getting 18" of vacuum in neutral idle and 16" in gear.

    GodStang, did adjusting the TP fix the code? If you can remember back that far?
     
    Last edited: Jun 22, 2011
  5. cobracide

    cobracide New Member Established Member

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    Try TPS = .98V
     
  6. Blown38

    Blown38 Member Established Member

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    Will do. I guess I should log the IAC duty cycle to see if maybe the TB blade is opened too much? I have another car with the same setup I work on and that thing pulls like 22" of vacuum at Idle. The only thing I haven't went back to was a stock TB and I can't now with the whipple inlet due to how the air is supplied to the IAC. I guess I could pick up or borrow a stock cobra TB.

    But as far as I can remember our car has always pulled 18". Maybe just a variance in gauges.:shrug:
     
  7. cobracide

    cobracide New Member Established Member

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    One quarter turn off completely closed on the blade is a good place to start.
     
  8. Blown38

    Blown38 Member Established Member

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    Ok I checked the TP. It was at .97 with key on engine off and 1.00 engine running. So I set it to .98 engine running and also adjusted throttle blade, idle was hanging slightly. Cleared the KAM. Dad just took it for a drive and the P0068 has not popped back up yet. We are going on a longer cruise tomorrow so I will post up if all is still well or not.

    Thanks for the input. It was interesting how the voltage output of the TP was greater with engine running. On the Predator it didn't go into part throttle mode till 1.05 TP volts.
     
  9. Blown38

    Blown38 Member Established Member

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    About 180 miles worth of driving today and all is good so far. Just need the evap system to come online now.
     
  10. cobracide

    cobracide New Member Established Member

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    Must be under 1V and no less than .96v. Key on engine off.
     

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