Car Stalls

[Guest ez211]

I have a 1990 Skylark with 3.3

It starts and runds till it wams up then motor quits

wont restart till cools off

have replaced the coil igniter

any other ideas/car has only 69000 miles

[Larry Schramm]

Does the engine have a black mass air flow sensor located just after the air cleaner? If so start the car and then tap on the maf lightly and see if is stalls. IF so it is the MAF.

Another common problem with those vehicles was the crankshaft sensor. It is located behind the crankshaft pulley and gets signals from the openings on the back of the pulley openings.

And as always be sure to put a pressure gauge on the fuel rail to check the fuel pressure. If my memory is correct the low spec is 45 pounds. The car may start and run monentarly at the 45 spec, but it should be higher. Check a book for the specification, but I think it is in the high 50's for fuel pressure to run correctly.

[rick60]

All of the above is most likely the cause of your problem. There is one more thing to check. If one or more of your fuel injectors have low resistance the car can start and run, the stall. All six of the injectors are controlled by one quad driver in the ECM. The quad driver is designed to open circuit the same as a circuit breaker in your house. This is done to protect the ECM. Low resistance results in higher current flow. The injector resistance will increase as the engine warms up. When the quad driver opens all six of the injectors will not be supplied with voltage. You can disconnect the electrical connecter from the injectors one at a time to see if the car will continue running. It's been so long since I've worked on one of these cars that I don't recall the resistance specification. You can measure the injectors one at a time and look for one or two that have significantly lower resistance than the others. Good luck.