I have a 1999 Z28 with LS1 engine and auto tranny. The transmission seems to go in and out of overdrive when the car has 4 people in it. I was told by 2 GM certified mechanics that the system was forcing fuel through the lines because my fuel filter was dirty, and the engine was starved for fuel. Well, changed the fuel filter, fuel pump is still working fine, but still having the problem. Is it possible that the lock out solenoid in the transmission has gone bad?
