bmiddleton7198

Hello all i have a 99 gmc ecsb with a 5.3 full bolt on built 60e, yank tt-3000, 4.10 gears posi. And so on my issue is that the converter keeps locking and unlocking even in od at 70+ mph cruising.. the code thats bein thrown is the P0751shift A solenoid performance or stuck off.. i have the tune done with efi live and only deleted torque management and raised shift points and love the way it shifts. I recently added e fans and 160° stat and have the fans working when i turn the key on ive heard that with the weather being so cold that the motor must get too 140 for the converter to lock up and im thinking the motor mite not be gettin that warm.. any thoughts or suggestions will be appreciated much

nonnieselman

iTrader: (10)

Do you have EFI Live?

bmiddleton7198

Yes tuning is done with efi live

bmiddleton7198

Well lil update the weather has warmed up and motor gettin hot enough is not the issue.. and i forgot to add in the first post that when the converter decides to lock up after much driving it shutters and causes the whole truck to shake really bad but it never stays locked longer then a min or so.. It shakes So bad that at first before it was throwing a code i thought the engine was missing. Any help and advice would be much appreciated.

skeet

iTrader: (18)

this a new Yank or a used Yank ?

Vince B

iTrader: (1)

The shift solenoid code relates to a 1-2 shift solenoid that is basically on in 4th gear. If it were bad I would think that you would loose 1st and 4th gears. I'm curious if the issue might be tune related and you might have to delete the test for the PO751 in your tune. I suggest this to most people I build units for along with the PO757 and never have issues like the one your having. I'm curious if what you are feeling is the trans actually falling out of 4th and then going back in. Just a thought. Vince

bmiddleton7198

Skeet the yank has been in the truck for 1 1/2 now.. and nice truck ive seen it run at evadale before..

Vince.. thanks for the reply i think if it was falling from 4th it would just free rev then try to go back into gear but its just unlocking and flashing up to 3000... as far as the tune its been doin just fine withe the tune thats in it for over a year now. As soon as the laptop get back for repairs ill be deleting code.. thanks for the help

Vince B

iTrader: (1)

Make sure to clear the code and then delete the test for the code.

bmiddleton7198

Vince as soon as the laptop makes it home from the repair shop thats the first thing ill do.. once again many thanks for the advice.

08VMAXZ71

Is the P0751 code only available to turn off with EFI? I'm just not seeing in with HP Tuners. Sorry to butt in on the thread.