The transmission pressure control solenoid may fail causing erratic shifting. Our technicians tell us that partial dis-assembly of the transmission is necessary to replace a failed pressure control solenoid.Google+
Car Problem Reports
Pontiac Grand Prix GTP Transmission Pressure Control Solenoid Failure May Cause Erratic Shifting
Pontiac Grand Prix GTP Problem
Average Mileage: 144,828 mi (132,000 mi - 157,657 mi)
Visitor, 2002 Pontiac Grand Prix GTP, 132,000 mi
my transmission intermittently shifts hard in all gears.