Pontiac Repair: cant find it, grand prix 3, dosent work

Question
I have a 91 grand prix 3.1 6 sylender,that runs for a while then dies and wont start for a while, but eventually it will start and run then die again. i have ruplaced, plugs,wires,coil,computer,and now have the crankshaft possion sensor,but cannot find it on the motor. we looked on front of motor not there were else could it be? and if this dosent work then what do i try next?

Answer
before you spend any more money and waste it go and let a shop use the computer and see what happnmes why and when it quits for the 40.00 you will be money ahead

simply trying to help , but it seems you keep spending money , im sorry you feel i cant help you but without testing the computer and reading the outcome from that its very hard to diagnose your problem.. i still say get the computer read and then go from there