hello all, I have a problem. I have the 200r4 tranny in my 85 ss monte carlo. I recently took out the computer and have since switched the lockup control over to a manual switch in the car. I have done this setup on three different vehicles ive owned and never had a problem. The problem is once i lock the solenoid, it will stay locked up even with power off to it. The transmission seems to shift fairly hard, but the owner claimed it has always done this. (older guy and very honest about everything on the car). Recently, i had all new transmission seals installed. (it was leaking BAD) The car had set forever and the seals had dry rotted i guess. He put new seals in everything. He even put me in one new band because he said it was a little burnt. I had him put me in a brand new lockup solenoid since i figured that was why it was sticking to begin with and it would be a perfect time to replace it. Well, i got the car back and the tranny shifts great, doesnt leak at all, but the damn solenoid still sticks. I can drive it around forever, but once i lock it, it will stay locked until i shut the car off for a while and i guess the pressure lets whatever is sticking un-stick. I dont know what is causing this. I mean it drives great, shifts great, and the lockup works perfect when i hit the switch. Its just when i go to unlock it, its still locked.

Sounds like a sticky solenoid switch. Need to drop the pan to replace. NAPA has them.

solenoid switch? So your telling me there is a switch that controls the actual solenoid? I have replaced several solenoids, but never a switch. Some sort of pressure switch i presume?

Did you do the external manual lockup conversions or the internal? If internal type is uses the 4th gear pressure switch on the bottom right side of Valvebody that may be sticking.

When the 1-2 shift valve strokes it supplies fluid to the TCC circut.

But only when the 1-2 valve moves to the upshifted position.The fluid "supply" is shut off when the valve moves back to the downshifted position, so as not to allow lockup in first.

Therefore you can not achieve lockup until this occurs, unless the TCC solenoid is faulty and allows the lockup valve to stroke or stay applied even after the 1-2 valve has reached the downshifted position.

A very common failure at one time, the solenoid would fail and flood the TCC circut, thereby causing the TCC lockup valve to stroke to the lockup position.

Coasting to a stop and feeling a jerking situation was a common symptom which indicated a TCC solenoid that was not releasing it's supply of fluid and in essence hydraulically applying the TCC lockup valve.

well, its not locking up in first. I mean I can come to a light, and the car doesnt jerk around like its locked up. I know what it feels like becuase on my old truck i would sometimes forget to unlock it and it would almost stall. As soon as it shifts though you can tell its locked up and will stay locked up through all the gears and even with the power to the switch off.