peterl2111

Ok, so i have a 1988 iroc-z with a 350 tpi and 700r4 tranny. the car is completely stock. the car was my fathers and sat for roughly five years before i began to drive it. when i started driving it i noticed the car didnt lock up at all. having an auto class at high school before i graduated, my teacher recomended i changed the lock up solenoid so i did. however this did not solve the problem but made it worse. now when driving it i couldnt keep the rpms steady. the rpms continuously bounced up and down, like it was constantly up shifting then quickly downshifting and this would just repeat. it got to the point to where it was undrivable. running out of time in the auto class i just disconnected the solenoid from the top of the tranny and left it at that. with the solenoid diconnected the car drives like it did before i changed the solenoid, perfectly fine but with no lockup. any ideas on whats going on here? any help with this would be very much apreciated, thanks in advance.

Floor guy

I am suprised a teacher recommended throwing parts at it, without proper diagnosis.
Drop the pan, and identify the pressure switches screwed into the valve body. Once you determine if they are normally open, or normally closed, remove them and apply air pressure to the back side of them. Using a continuity checker listen for the beep, at the proper time. If the solenoid, wiring and pressure switches check out, look to the brake switch to see if it is out of adjustment.

peterl2111

Alright buddy thanks for the help. If all this checks out, anything else i should specifically look in to?

Floor guy

Physically inspect the wiring harness in the trans, as well as the connector on the outside of the trans. Be sure terminal A has 12 volts with the key in the ignition position.
Also verify proper brake pedal switch adjustment inder the dash.

peterl2111

ok, well just incase anyone was curious or has a similar issue, the problem is believed to be found. i gave the car to my mechanic who, after checking all the possible minor issues, sent it to a transmission shop. according to them, the third and fourth gear clutches are worn and led to all the issues.