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HELP! Car only idles after TPS calibration

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Old 09-10-2011, 12:56 PM
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Default HELP! Car only idles after TPS calibration

Stupid car. I swear, I always take one step forward and eight back.

Found that the negative battery cable had a bad fray on it leading to an occasional no start condition. I fixed that with a ring terminal, and the car never ran better after doing that.

I have been working on getting my basic tune set for a while, so I haven't removed the overboost limit yet. I upped it from 152 to 179 and burned to ECU. Then I recalibrated my TPS. Oddly, the last time I tried to do this, I couldn't get it read 100% at full throttle. This time, it read the full sweep like a champ. I chalked it up to my bad ground.

But when I went to pull the car back into my driveway, it stalled. For whatever reason, I can't rev the car out of idle. I can slowly SLOWLY give it gas (not changing the MAP reading) and it will rev all the way to redline, but giving it any kind of gas at all leads to it stalling out. My wideband shows full lean when it does this.

I don't know what I'm doing and I'm ready to kick a small animal through a brick wall.

Any assistance on what to check would be great.

Thanks,
Trent
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Old 09-10-2011, 01:21 PM
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Sounds to me like AE is drowning the car. Are you using TPS-based AE, or MAP-based? Note that once the flame extinguishes, the WBO2 is going to read full lean (i.e., lots of O2 present) even if you've drowned it with fuel.

You might start by cutting your AE way down (maybe even 0), and then just increase it little by little to address lean stumbles.
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Old 09-10-2011, 01:28 PM
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I went into the acceleration wizard to check. It is completely map based. I put all the ms values to 0. No difference.
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Old 09-10-2011, 02:09 PM
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Update. Got it fixed. I am an idiot.

I had the laptop in the passenger seat, so I plopped into the passenger seat to work on it. When I did that, I pushed the seat back. To do that, I shoved my feet into the footwell. When I did that, I crushed the vaccuum line going to the MAP sensor where it slips under the footwell. D'OH!

Uncrimped it and routed it better to prevent this from happening again.

Thanks for the suggestion hornetball.
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Old 09-10-2011, 02:44 PM
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Good deal.

BTW, you might want to try the TPS AE. On mine, the MAP AE would give little shots of fuel during cruise simply due to MAP noise. Do some logs and watch for it. It will show up as rhythmic fluctuations in AFR. Switched to TPS AE and problem solved. The TPS signal tends to be very clean.
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