Got my car back last night after having some drivability issues with my new transmission (built in late Dec). Basically the car was slipping at full throttle from 2 to 3 shift. I took it back and dropped it off while I was in FL for the ISSCA meeting. Picked it up last night and the shop owner informed me that it had already burnt both clutch packs! He had seen low tranny pressures in a previous 1/2 day drop off to diagnose but he had thought it was my programming so I returned it to stock. Well come to find out:
FIX is here

The wire from the force motor to the PCM and another one was shorted - causing low pressure and slipping.

By fixing the wire it also fixed some other issues I was having:

1. High idle - car would idle around 1500 rpm as I would slow to a stop and then stay there for an extended period of time

2. "Miss" from 3000 to 5500 rpm under load - miss turned out to be tranny slipping/surging as wire shorted/opened

My car shifts solid now - I went with the "back breaker" 3 washer setup and he did the full "heavy duty" treament as he called it. He is warrantying the car for 12 mo / 12K miles with juice

Car also now chirps 2/3 at anything over 1/2 throttle...

If you're going through trannies check that wire!

Mike

 

Do you know what the wire color is? Where was the short taking place? What caused it?

 

I only know the generic details I was given. It was the stock wire that goes to the tranny and it was chafed inside the harness with another wire and they were shorting each other from what I was told.

Mike

 

Did your car exhibit a pulsation at low speed / low rpm in overdrive? Pulsation and vibration at 48 - 60. If you accelerated, did the pulsation / vibration stop? Did you experience vibration or pulsation in deceleration in overdrive (coasting from 55 - 45)?

Obviously, I'm trying to relate my problem to yours )

Thanks for the input.

 

Maybe this is the issue we all have been having with missing at high RPM's under load ??????

 

I didn't have a pulse when cruising no. I did have a bouncing idle at rest though. I may have fixed that by opening my TB blades a little - I have a Holley 58MM TB.
Mike

 

Thanx for sharing the info.

Help solve some of the LT1 stumble issues.