At night when the weather is cooler my engine idles under 1000rpms and runs fine. But during the day when the temperature is warmer my engine idles around 500rpms for a few minutes then starts idles at 200-300rpms and stalls out most of the time. I am going to change the fuel filter out and see if that's it. I was going to idle the car up using that idler screw but I'm not sure were it's at. Should I change my IAC valve? Any opinions, thanks.

 

P.S. If I put my A.C. full blast it seems to idle fine, but if it's off or not full blast then it starts acting up.

 

Turn up the idle and get back to us... using the AC just bumps up the idle.

 

could be a bad voltage regulator... clogged up TB, cold idle sensor, etc...

 

Will do and get back.