When does the lock up engage.

Still having the surging problem on my 2000 GT. Wondering if it is related to the lockup converter. Does anybody know what conditions the computer has to see before the converter locks up?

generally, holding a steady speed above 40mph for a few seconds will activate the TCC into lock-up

generally the ECM has to see 3rd gear and temp,,,,warm drive-train,,,
to "lock" the converter.........NOW,,,, the trans,,,,takes the torque signal
from the engine and delivers it to the wheels,,,,,,{the car goes down the road},,,,IF,,, the signal is crappy {from the engine},,,,,,,,DON'T expect the trans to deliver a quality output.....now if the converter is
locking and un-locking,,,,thats different,,,,,,but you will have to put a little thought into where the problem is coming from,,,,,,hope this helps!!!

the way it sounds is that your converter is locking and unlocking. you should depress the brake pedal(just enough to cause the converter to unlock) and hold it there all the way to the top of the hill. if the rpm holds steady then you could tell if its the tcc, locking and unlocking . if it is the tcc and its getting a bad signal then maybe could look for a vacuum leak. i had a similar condition in my truck, good at cruising, but come a hill start surging. turned out to be a leaking intake manifold gasket.

Thanks a lot guys. I really appreciate the info. I will try the brake pedal trick and if that narrows it down to the tcc then I will try to get a scope on the signal going to the lock up. Thanks again.

That did it, lightly touching the brake while it was surging made it hold a steady RPM. Now I need to find out why.

Hey all,

Me and drjimmy have the same problem (exact). If anyone knows what this problem is please post or reply directly to me. Mine is a 1999 GP GT.

Thanks,
Greg

That did it, lightly touching the brake while it was surging made it hold a steady RPM. Now I need to find out why.

I have seen bad TPS do it they do have problems with the tcc valve in the valve body wearing the bore out (PWM "pluse width modulated" stroking the valve to much).

i dont have a stroking problem:)

Odin, that cat's been on the net for like 2 year's.
why are you spamming thread's with that crap ?
you should be banned !

I dont get it....Is it supposed to be funny b/c its a "shaved feline", or b/c it just looks retarded?
Either reason its not that funny though.