TC Lockup parameters?
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Joined: Jul 1999
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From: Eagle IDAHO
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TC Lockup parameters?
Does anyone know the parameters and conditions that the ECM uses to lock and unlock the torque converter. Reason I'm asking is that my TC seems to unlock whenever I let off the throttle ever so slightly. Then when I press down on the throttle again, the converter slips slightly and then locks up. I have bought an LED setup for the ALDL to monitor this, but haven't done it yet.
Burning Brakes
Joined: May 1999
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From: Greenwich, CT
Re: TC Lockup parameters? (NHVett)
Um, not sure about an '85, but on later models TCC is controlled by a combination of VSS and TPS signals in the ECM. There are at least a couple of curves for lock/unlock in different gears. There is also what I think is a separate minimum speed condition for lock/unlock, but I haven't spent any significant time looking at that code myself.
Here is a typical TCC lock curve from a TunerCat display:
http://temp.corvetteforum.net/c4/doc...lock_curve.jpg
To know exactly what yours is doing you would need scanning/recording software (like Diacom) on a laptop to see where you are having the problem. To change the TCC conditions would be a matter then of burning a new PROM.
HTH
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Pro
Joined: Jul 1999
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From: Eagle IDAHO
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Re: TC Lockup parameters? (DOCTOR J)
Thanks, Doctor J. Maybe Craig Marcho will see this post. He has pretty in depth knowledge of 85, among others.
