1990 Pontiac Grand Prix automatic transmission

1990 PONTIAC GRAND PRIX
131,000 MILES • 6 CYL • 2WD • AUTOMATIC
Avatar
2CP-ARCHIVES
  • MEMBER
  • 4,540 POSTS
1990 Pontiac Grand Prix mileage: 131,000. I had the transmission serviced (fluid replaced) by our regular mechanic. After servicing it drove very rough when the automatic transmission would down shift it made you pitch forward/lurching as you slowed. I returned to the mechanic and he checked it over and stated that the only thing to do was to disengage the torque converter? This performs the shifting for an automatic transmission. Any other suggestions?
Oct 20, 2010 at 5:42 PM
Advertisement
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.
Avatar
2CP-ARCHIVES
  • MEMBER
  • 4,540 POSTS
Your car has a lock-up torque converter in the transmission. It locks-up only in high gear. It is supposed to disengage at lower speeds. Yours is not disengaging. There is probably a valve in the transmission “hanging up”. The torque converter is controlled by the TCC (Tongue converter clutch) solenoid. Replacing it should fix your problems.
Oct 20, 2010 at 6:03 PM