My wifes 2004 Chevy Impala had an issue about 6 months ago where the Fuel pressure regulator went bad and it was stalling after start as it would get flooded. After I changed it the car has been fine. I had also changed the plug wires and plugs around that time as they hadn't been done since we bought the car used. Recently it has been running a bit rough when idling. When trying to start it takes a long time to start (maybe 7 to 10 seconds of continuous cranking). If you press the gas pedal all the way it starts in around 3 to 4 seconds (still a little slow). When driving it has good power however if you are cruising and not touching the gas pedal it will sometimes stall. If I drive with the pedal depressed very slightly it will almost never stall. I removed and cleaned the IAC, and also cleaned the throttle body. I also tried unplugging the MAF sensor to see if that would help and it did not seem to. It has set a few Random misfire detected codes that keep coming back after a bit of driving.
Any help would be appreciated.
Thanks

 

Anyone ? Or is there a better forum for me to ask the question ?

 

We are having some similar issues. Did you find another thread? 2004 impala. Started to shake while idling. as time went on, engine would crank over but wont fire unless footfeed to floor, then still awhile to run. Runs high idle, andif you rev the idle, it goes higher, and then slow to go down, but never a slow idle again. We replaced spark plugs & fuel filter. Only code was for thermostat sensor, which we changed. Unhooked battery overnight. Please direct me to the right thread if no one can answer this. thanks!