I have a 1999 Bonneville SLE, with 190,000 miles, that turns over while starting, but sometimes has no spark. If it does start, it starts in an instant. An Autozone store checked for any codes on the computer and there were none. He said that he once had a Oldsmobile with a simular problem and he had to replace an electronic security module located under the dash by the steering collume.

It works great once it is started, but I dare not shut it off if I am away from home.

Any Ideas??

Frances

sounds like ign cntrl, or crankshaft pos sensor maybe, does it do it worse if the engine is warm before trying to start it

My initial thought is crank shaft position sensor.

The first time that it happened was about a month ago after the car was only driven a mile. The other 4 times that it happened is when the car engine was cold and would not start.

Hopes this helps.

No, most of the time the engine is cold.

usually those things i mentioned start to go and cut out after hot, sort of unusual but i would think its still some thing like that, unfortunately it hard to narrow down with symptoms like that

I'm sticking with crank shaft position sensor.

How about the cam shaft position sensor also???

How much labor would be involved to replace the crankshaft sensor?

Thanks to both for the info.

https://www.gmforum.com/mechanical-134/change-crankshaft-position-sensor-279066/

Since the engine is cold, my money is on the ICM or crankshaft position sensor.

Also, I moved your thread into Bonneville M&M 1992-1999. The gear heads live here.