My car has starting problems. When it finally starts, it stalls. I've got the battery replaced but the stalling continues. It occurs at low RPMs during idling. It runs a bit better after tuning it up. But, it still idles poorly and stalls at stop lights. I checked the alternator by disconnecting the battery. It runs well that way so the alternator is not an issue. What could be the problem?
A sticking or stuck idle air control valve can cause this condition. The valve needs to be removed and inspected for excessive carbon buildup. The valve could be cleaned and then then re-installed to see if proper operation can be restored, but these valves are inexpensive and generally just replaced. Fault codes should also be read out to see if there are any other possible issues as well. You may want to enlist the help of a mechanic, such as one from YourMechanic, who will have the tools and training to correct your stalling issue.