wont drive and p1750. rebuilt tcu

[ed1380]

vehicle in question is a 97 gsx auto with 115k miles.

I bought the car with a knocking engine, so I dont know the exact history of the vehicle. for the past couple weeks I've had it there has been trans fluid dripping from the pan gasket. Engine has been rebuilt with everything ready to go. put the car in D on the lift and all 4 tires spun, but didnt rev or anything.

back on the ground ready to test drive, put it in drive, feel the engine bog as normal, let go of the brake and it rolls forward normal. give it some gas and nothing happens. I let it go to 2k and the car just rolled like in N. reverse is even worse, because it's just like N. at least there was a little jerk when I put it in D.

So I added fluid and tried it again. I kept doing that until I added 3 quarts. still same results. This is when I checked for codes and got p1750 for transmission solenoid assembly. now i knew something was wrong so I seached and found the tcu codes. mine were 41, 43, 83, 84. pretty much open circuit on solenoid A and B.
I took the pan off(ended up draining a 4qts) and everything looks clean. oil was good, but then again I just added alot.

I tested all 4 solenoids according to the service manual through the external plug and they all passed the ohm test. I checked the tcu and it looks great. no leaking caps or burnt traces. it's an eeprom version that was rebuilt in 2008 according to stickers on it.

I'm really running out of ideas of what it can be. I'll check the wiring between the tcu and the trans tomorrow(actually today) but that is the last thing I could think of.

If anyone has any ideas of what it could be, please help me out

Thanks

 

[johnmarines]

When you dropped the pan.. should have been around 7 qts instead of 4.. did you properly check the trans fluid to verify it was full before you tried to drive it?

 

[ed1380]

Is that how much you ended up draining when you did yours? I did see that capacity was 7qts, but the torque converter should keep a few quarts. Can anyone confirm this?

It did look full when after I poured the 2qts, that's why I stopped.

well I spoke to a tech at IPT and that's about right. I actuallly poured 3 qts back and it was full. so TC takes about a gallon.

btw the o2 sensor and solenoids have the same plug and they're close to each other. hint hint. I swapped them back and everything works fine