1991 Grand Prix help

[donna dodd]

My 1991 Grand Prix has a 3.1 engine and over 100,000 miles . It dieded in the middle of the intersection with no warning lights or noises. My brother changed the plugs and said it was getting good spark. He then changed the fuel pump. The car started up but died 5 minutes into the test drive. Does anyone know what could be causing my problem?

[GTP Dad]

Two items, ignition module or the crank position sensor. Both can cause the problems you describe and are relatively easy to fix.

[walkin986]

hello i have a 91 grand prix se with over a 100,000 miles on it as well and it stalled while cruising at 50 mph and it stalled after wards every few hundred feet i had a new fuel pump put in as well but my problem turned out to be a bad fuel injector,it seems the bad fuel injector was screwing up the other ones ,the mechanic also said he never had seen a fuel injector problem of that nature before good luck

[MrEleven]

Ok so i am having this problem myself. Now heres the real catcher. I have replaced both the crank sensor and the ignition module. when the engine gets up to temp it shuts down. any clues?

[modfan]

i just had a 1991 grand am,2.5 l engine,givenn to me...i need to replace the crank position sensor,and would like to know the best way to get to it...if it is between the engine and firewall,under the dis assembly,it looks pretty impossible to get to....any suggestions as to how to access this area to replace the sensor? thanks!

[maxwedge]

Originally Posted by MrEleven

Ok so i am having this problem myself. Now heres the real catcher. I have replaced both the crank sensor and the ignition module. when the engine gets up to temp it shuts down. any clues?

You need to check for spark and injector pulse when this happens, step one in diagnostic procedure.

[frogman6042]

was having problems with mine and it was the computor changed it and the car never ran so good i would try a used one first i went to salvage yard and got two for 15.00 now i have a spare good luck...

[richtazz]

If your GM service number is 1227227, buying a used one is a crap shoot. They have a high fail rate due to being under the hood and exposed to the elements. Do like Max said and check for injector pulse when it dies. If it has no inj pulse, it's the computer. You can also "tap test" it. Tap lightly on the ECM while the car is running and see if it dies, or tap it when it won't run and see if it starts. If either is true, the ECM is bad.