2000 Saab 9-5Aero 2.3L HO4cyl. 108,000 well-maintained miles
With increasing frequency the engine will, when idling, stumble and stop. Weather, cold or hot seems not to influence the event. Re-start attempt is: vigorous cranking by starter, electrical power no problem, but engine won't start. Sometimes a jump-start will work, most times not. Once the car sits, off, for a time, (varies), it will start as normal and the phenomenon may not occur again for days. There is no detectable fuel odor, electrical connections, alternator (new), battery, etc, are all good. Engine runs smoothly with no unusual exhaust nor misfiring. If I'm quick enough, I can apply accelerator at first sign of stumble and prevent stalling. So, my guess is it's a fuel problem, but injector, pump, or? Any help by way of diagnosis and/or advice will be welcomed. I plan to have a dealer check it, but, frankly, I have neither much confidence in them, nor trust them to deal honestly.