Vacuum leak is one cause. ----- Another possible cause may be a bad Idle Air Control Valve (IAC Valve). Your car should Idle, once the engine is at operating temperature, between 680-750 RPM. If the engine idles below this range with no appliances on, i.e. Air Conditioning, Fan or Window Heat, then your IAC Valve may have gone bad. SUBMITED: Friday, 03JUN11
The engine needs fuel, compression and spark to run, one of those is missing. Being a GM product my money is on a faulty fuel pump.
Leaking head gasket? Any signs of water in oil or oil in water? When engine it hot remove oil dipstick and let a drop fall on hot part of engine Oil will smoke Water will sizzle
Bad gas, fouled plug(s), engine out of time, vacuum line leak or clogged.
Stalling at idle? Immediately after starting? While driving? While stopping? Cold or hot engine? What engine do you have?
Crank angle sensor
You've run out of fuel...
get an engine diagnostic scan.
it might cause starting problem, low/ lesser pickup while pressing acel., missing.
The most common cause for surging is a vacuum leak
Engine miss.
Gasoline pedal/air intake pedal