I had a bad alternator it was putting out barely 12v. I started to have a rough idle and it was idling at about 500 RPM. It stalled twice. I replaced the alternator and it is charging properly. Sometimes it idles around 500 or less and then the computer seems to catch it and raise the idle. Any ideas? It only seems to affect idling because it is driving normally. Could it have fouled the plugs when it stalled due to a weak spark?

 

hmmm seemed okay this morningon the way to work.

 

try unplugging the battery for a bit to reset the computer? just a something to think about doing