1998 grand prix transmission problems

[thecrow1986]

my grand prix is having some problems its a 3.8 v6 and has a 4 speed automatic electronic transmission with traction controll. the problem im having is with my transmission in the morning after the car has been siting overnight the car has some problems when i put it in gear it bucks and when i get it up to about 19 miles per hour it bucks again then around 35. sometimes it has a bad vibration but it will go away if i give it some gas. the engine light will come on when it has these problems i got i checked and the only code was ( torque convertor circuit stuck open) the thing is after i drive it for about 10 miles or when i gets warmed up the car is fine and it has no problems. you can floor it at anytime and it will take off with no problems so i dont think its the transmission maybee a bad tcc sensor , i dont want to change the transmission if i dont have too please help

[BNaylor]

It would help to post your mileage and the model of your Grand Prix.

When was the last tranny service.....ATF and screen filter? What was the specific DTC? It sounds like the TCC is stuck on meaning you may be having problems with the TCC-PWM solenoid which is located on the valve body internal to the transmission.

[troy1]

sounds like it could be a solenoid or a sticky valve. Some valve bodies use an aluminum valve in a aluminum valve body which does not work so well. But the bad news is if the valve is sticky there might be other problems.

[thecrow1986]

Originally Posted by bnaylor

It would help to post your mileage and the model of your Grand Prix.

When was the last tranny service.....ATF and screen filter? What was the specific DTC? It sounds like the TCC is stuck on meaning you may be having problems with the TCC-PWM solenoid which is located on the valve body internal to the transmission.

132,000 miles se, i have no idea when the last transmission service was i was told a year ago but who knows i havent had the car that long. the code was po742. someone told me maybee i should try seafoam? it might help they said

[BNaylor]

Yeah the P0742 DTC properly translated means the TCC (torque convertor clutch) is stuck on. When this DTC sets it disables shift adapts and the TCC is commanded on at full capacity which would be consistent with your symptoms. You can try the Seafoam. Nothing to lose at this point in time. Run the full 16 oz of Seafoam for a couple of hundred miles. Then do a pan drop - ATF and screen filter change and then see what it does. Good luck!

[thecrow1986]

Originally Posted by bnaylor

Yeah the P0742 DTC properly translated means the TCC (torque convertor clutch) is stuck on. When this DTC sets it disables shift adapts and the TCC is commanded on at full capacity which would be consistent with your symptoms. You can try the Seafoam. Nothing to lose at this point in time. Run the full 16 oz of Seafoam for a couple of hundred miles. Then do a pan drop - ATF and screen filter change and then see what it does. Good luck!

ok thanks for all the help ill put some in and see what happens after i get the fluid and filter change, i was looking at the fluid today and it looked a little on the burned side so its probably not helping. do you know where i could get some sea foam?

[BNaylor]

Originally Posted by thecrow1986

do you know where i could get some sea foam?

Off the top of my head both NAPA and Autozone carry Seafoam. Good luck.

[thecrow1986]

Originally Posted by bnaylor

Yeah the P0742 DTC properly translated means the TCC (torque convertor clutch) is stuck on. When this DTC sets it disables shift adapts and the TCC is commanded on at full capacity which would be consistent with your symptoms. You can try the Seafoam. Nothing to lose at this point in time. Run the full 16 oz of Seafoam for a couple of hundred miles. Then do a pan drop - ATF and screen filter change and then see what it does. Good luck!

is it a good idea to have the transmission flushed or just drop the pan and change the fluid and filter? im having a debate with a friend i believe i heard somewhere that flushing my cars transmission at its age and milage might hurt it because of the gm pressure system. what do you think?