2000 Buick LeSabre 3.8 V6
It starts then dies as soon as it starts. I replaced the fuel filter. Didn't help. I checked the fuel pressure. 48 pounds with key on. As the engine starts fuel pressure drops slightly then goes up to 50 to 52 pounds as it dies.
Sometimes if I pump on the throttle it will rev up to about 3000 RPM then it dies.
I acts as though the ignition switch might be going out. In the old days (When cars had points and condensers) the ignition switch would give the points full voltage when the switch was turned to start, then as the switch was released from start and returned to rum mode, voltage to the points was redirected through the ballast resister. If the switch went out on the run position it would start and run in start but die as soon as you released the switch.
This is how it acts except it won't continue to run if the switch is held to start, or released then turned back to start.
There are a few simple tests you can do. Get your self a spark tester. This is a special light that goes between the spark plug and the spark plug wire. As the car starts observe the light, if the light does not flash or goes out when the engine stalls then it will most likely be a spark issue.
A fuel system noid light can be used to identify if the fuel injectors are shutting down electronically. All you do is take off one injector wire and insert the noid light. If it starts flashing and then goes out or does not light at all then this may be a electronic issue in the fuel system.
A scanner or code reader can be used to help identify any trouble codes that may be causing the engine stall. Repair any codes that may come up.
Does your car have a factory installed security system, and if it does is the security light on?
If you have a factory installed security system, it is possible that the security system is shutting down the engine. The chip or sensor in the ignition switch could be faulty. If the security module doesn't see a signal from the key it could shut down the engine. Try using another key to start the engine.
Try these suggestions and let me know how you make out.
Thanks for your suggestions. Sorry for the delay, I haven't been able to look at the car again until today.
I checked the spark and it has spark until it dies. The spark is consistent even as the engine starts to sputter and die. I don't think this is a spark issue.
I don't have a noid light. I will get one and check it out.
There is no check engine light but I plugged the scanner in anyway. There were no codes.
There is no security system. I tried another key without success.
There is one other peculiar thing. The warning bell that sounds off when you leave the lights on or leave the keys in the ignition ring as soon as the door is opened regardless of weather the key is in or not. It continues to ring until the door is closed. I don't know if this is a clue but it started doing this about 3 weeks before the car broke down.
It probably needs a headlight switch for that problem but I thought I would mention it.