What could it be when you drive your car for about 10 minutes completely stalls and dies no spitting and sputter just loses power? I have replaced the cars altinator and ignition module what else could it be?
Can you restart the engine immediately after the stall? If you cannot, have you checked for the presence of spark and reaction to starting fluid squirted into the intake? If this has a single coil and distributor, I would look at them. I would also check the fuel pressure both at idle and under heavy load. Next would be the Crank Position Sensor, then the Cam Position sensor, and then the fuel filter and fuel pump.
As you can see, fixing an intermittant without narrowing the problem down is a shot gun approach, i.e. replace parts until the problem goes away.
I googled a 1995 Pontiac Grand Prix 3.1 liter and found it has a low resolution Crank Postion Sensor, a high resolution Hall Effect Crank Postion Sensor, and a Cam Position Sensor. The low res CkPS is used for starting only so that is unlikely the problem. The high res CkPS is solid state so it might be thermally sensitive. You are going to have to check Alldata to find out where this is located and google to find out the cost.
Hope that helps.
Sometimes it will crank immediately after it dies sometimes not. The fuel is holding pressure i had a mechanic look at the problem they couldnt find anything wrong with the fuel parts. The replaced the altinator which was apparently not the problem. I kind of got mad because they didnt fix it when i paid 334 on the stupid car…