1997 Buick LeSebre

Car run great, Except, for no apparent reason it will shut off while going 55 mph. Have had it to two garages (one was a Buick dealer) Machanics have hooked it up to the diagnostic machine and no lights come on. It went 3 weeks and 400 miles without this happening. And, the last Sat. eve. it happened again. After a min. it starts up and run good. That is until it stops again. Can anyone hdlp with this?

when was the last time you had the fuel filter replaced? If it has been a good while start there.might not be a bad idea to check the fuel pressure when it happens. I’m surprised the shop didn’t already do that.

I have also seen coil packs that were starting to go bad do the same thing…but usually the car will start to miss really bad first…and it usually takes a few minutes before the car will start up again.

Just because I have seen so many bad GM fuel pumps I go for it,even if the pressure shows good.I have seen them towed in you go to bring the car in (with the pusher and help) and the car starts up and drives in,But dont dare say no trouble found or could not duplicate.

Thanks, sounds like a good place to start. Yes, the shop did check the fuel pressure. It was O.K. but they couldn’t get it to die while they had it, so didn’t check the fuel pressure when it happens. It will be O.K. for 2 to 3 weeks and be just fine. Wish it would die and not start, they maybe shop could fix it. Thanks again. Jan

Took the Buick to have the fuel pump checked, the machine did not give a wavey line, but a rather straight line. So, the fuel pump was replaced. Drove the car about 100 miles and it died again. And, this time it didn’t want to start. Took several tries before it started. Have been told this sometimes happens with these cars, and the problem is never found. Thinking about replacing the whole car. Hummm, what do you think. Here we are out about $400.00 and the car is still the same.

Has the check engine light ever come on? If yes, what were the codes? If it has codes, those could help in diagnosing the problem.

For an engine to suddenly cut off, it is (generally) from an electrical fault, or an ignition fault…possibly, the ignition module. The appropriate test should be done before any parts are changed.

Problems can be caused by electrical connections becoming oxidized. Simply disconnecting all the connectors, especially those to the ignition module, examining the terminals, and reconnecting the connectors will have a wiping action and result in good electrical connections.

Some ground wires bolt to the parts or the car body. Rust happens, and is an EXCELLENT electrical insulator. Sanding and lock-washers will help to restore conductivity.

Throttle position sensors used to be one of the causes of stalling at cruising speed. An insane computer will give no codes. Those are my best guesses, but they are only guesses.