1998 Buick La Sabre stalling

1998 Buick La Sabre: driving in parking lot, with no warning car stalls, starts up, stalls again…when driving, it stalls at uneven intervals…checked by mechanic found nothing…drove on freeway for 14 miles, tried to stall again twice…I know you can’t pin point trouble over internet,just give me something to work with.

A number of things hypothetically can cause this, and I am not qualified to report on most of them.

One common cause of stalling is often overlooked for something harder. That is, an idle control. Do you have a tachometer? IF so, get used to watching it, but please, don’t watch it so much you have a wreck.

With experience, you will see when you start the car cold, it should come up to a higher than normal rpm, smoothly and stop right where it should. Then, as it warms up, it should drop down to a modest idle speed, 750 rpm seems to be common idle speed for a warmed up car.

When you pull the car into gear,it should stay rather stable, not drop way down then wander back up.

If it ‘oscillates’ or does not return to idle smoothly, that can be a sticky idle control. That car is old enough that one would expect it.

There are some indications it might not be that. For example, if it stalls on the highway at highway speed at high rpm because your foot is on the throttle, that would not be an idle issue.

It is a hard thing to explain to those who do now know it, but easy to spot once you know it, sorry.

Thank you so much will run it by the mechanic…