The car just quits

Driving this 1996 Buick Century limited,4 cylinder car normally, the car will just stop running without any warning, nor rhyme nor reason. Most of the time this has occured, a tow truck has been called, but prior to towing, the car started normally and ran without problems for quite a while. The car has been in the chevrolet garage multiple times, at least over nine, for this problem, but will never show up for the mechanic. There is no specific driving pattern to cause this to occur: it dies in normal driving on the street, starting from a stop, in parking lots,

Carry an extra spark plug in the vehicle. The next time the engine stalls, remove a spark plug wire from one of the spark plugs and insert the extra spark plug into the end of the wire. Lay the spark plug somewhere on the engine so it’s grounded. Have someone try starting the engine and see if there’s a spark at the end of the spark plug. If not the problem might be with a defective crankshaft position sensor or a defective ignition module.

Tester

My bro-in-law states this has been done - the crankshaft sensor replaced twice. hankey

Hmmmm…the crankshaft position sensor replaced twice. I smell a check engine light and some error codes. Report em if you got em.

It might also help to carry some starter fluid with you when the trouble happens again. Spray a small amount into the intake and see if the engine tries to start then. If you get no response then the ignition system is most likely not working. If the engine runs briefly then there is a fuel problem. The fuel pump relay possibly. If the ignition system is the trouble there may be a problem with the ignition switch or in the power lead to the ignition. Testing needs to be done to verify power is getting to the ignition system.

I battled this problem for months with my Buick and finally just junked it. Crank sensor, ignition switch, fuel pump, relays, induction cleaning, etc. etc. I’d drive around with test lights and pressure testers on it trying to find the problem. Thought I had it fixed after the ignition switch but after two months started again. Not saying you won’t find the problem but intermittants are aggravating and costly and hard to find. If you do get a code though and says crank sensor, check out the wiring harness and connectors for the crank sensor.

I appreciate the input, and thank you for it. As nice as this auto is, it is rough to just junk it.

When I am dealing with an intermittent problem like this, one of the things I do while I am scratching my head is dump a can of Heet in the fuel tank to eliminate the possibility that it is water in the bottom of the gas tank. A time or two, it helped!

Ignition modules are a fairly common failure on these cars. I just replaced mine for the second time in six years for a similar problem. They are a much more common failure than the crank sensor. I would try to catch the car in failure mode first and verify there is no spark before replacing the module, though. It’s kind of a pricey part to just throw at the car and hope it fixes the problem (around $100, maybe a little more). If it’s not spark related, the fuel pump is a reasonable suspect, given the vintage of the car.

If the starter fluid trick I mentioned earlier failed to make the engine run I would have to think the ignition system has a problem. In that case the first thing I would want to know is if power is getting to the system. Knowing where to test the connection to power to the ignition is at and having at least a test light probe on hand would be a good step in finding the source of trouble.