Adjusted Idle, now runs like trash.

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DRFTPUNK
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Adjusted Idle, now runs like trash.

Post by DRFTPUNK »

So after resolving some issues (flywheel bolts loosened) I put my car back together and she was running pretty great. For about 2 weeks. AFRs around 14.5-15.5 at idle, idling at around 1k. I double checked the timing with a light and it was maybe advanced just a touch but close to 20.

Yesterday I was putting back together odds and ends double checked the timing and went for another test ride. She ripped really well and pulled hard. When I came back to the shop I was still just a bit irritated that the idle seemed so high so I wanted to drop it down to 7-800ish. This is where the problem started.

I unplugged the mafs, TPS, IACV and attempted to set the idle using the throttle body screw, not the one at the rear of the plenum. After that it went to complete trash. I even tried to set it back to the way it was before using the normal FSM procedure... but nothing worked. The timing now spazs out and is misfiring and my AFRs went to 16-17+ at idle.

Is there some sort of 'safe-mode' it might be stuck in? Where I'm somehow fighting myself on the timing/ idle air?

I have an RS Enthalpy tune and it was running awesome just a bit ago. I don't see how such a little input change wouldn't be able to be reset?
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tuzzio
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Re: Adjusted Idle, now runs like trash.

Post by tuzzio »

When you adjusted the idle at the throttle body, did you also adjust the IACV?
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p00t
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Re: Adjusted Idle, now runs like trash.

Post by p00t »

If you adjust throttle body screw your throttle sensor needs to be adjusted to 0.46-0.48v at closed throttle. Otherwise the ECU loses track of closed/open throttle and will not drive well.
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