Have 1987 S-10 Blazier, 2.8 engine, 4 spd. After running out of gas, and adding some, the gears won't shift. with engine on. I turn engine off and can get into any gear. Clutch seems to have enough pressure. So I turn engine off, put gear in 1st, turn engine on and vehicle takes off witout hitting accelerator, but cannot shift at all while running.