try changing the throttle position sensor
it is more than likely your transmission mabey a sensor of some type but its in your transmission
If your 1994 Pontiac Trans Am randomly stalls out while driving, you may have clogged fuel injectors or a bad distributor. Check the distributor first, as this is the easiest to replace.
crankshaft position censor
probably a bad camshaft sensor.
probably fuel filter or a simple tune up
There are a few reasons why a Pontiac 3.4 liter engine may die while driving. The battery cables may of come undone, a spark plug may need changed, or the fuel pump could of stopped working.
First guess would be the pick up coil in the distributor
the problem may be that the timing chain or belt has broken
Had the same problem and come to find out that it was the cars computer malfunctioning.
My 1999 Pontiac Montana would seem to "skip a beat" while driving. It then started stalling and restarting, all while driving at highway speeds. My mechanic found that an electrical cable that carried an engine sensor signal was leaning against a hot part of the engine. The cable insulation had melted or worn through, causing intermittent shorts. The shorts confused the engine computer, which then stalled the engine. He simply rerouted the cable and all was fine after that.
Some things that can cause a car to stall while driving it include a bad fuel pump, running out of gas, and low fuel pressure. A clogged catalytic converter can also cause this to happen.
A faulty alternator will cause those symptoms. You might want to get t checked out.