I don't think the torque converter is locking up on my '84 vette. I just bought the car, is it suppose to? On the interstate I never get better than 18MPG. My '86 El Camino locks up. How do I check or what do I check.

 

Many people with disable the lockup feature. They do not like how quickly the trans shifts into top gear. Most do this by cutting a wire. If I remember correctly it would be one of the wires going to the switch at the brake pedal. Many after market companies’ sale a kit to allow driver control of the lockup.