I've been having problems with my idle lately. When just sitting, it will surge between 1000 and 1500 RPM. I noticed lately, that if I leave my A/C on, even just on low, it will idle smoothly, although a bit high - somewhere around 1100 RPM. I DO have a CEL, P0171 - Bank 1 Lean. I have already replaced EGR valve, IAC valve, PCV valve, plugs, wires, MAF sensor, both 02 sensors, ECT sensor, TPS, and have checked battery and alternator, both good.
What I was wondering - Is there anything that gets bypassed when the A/C is turned on? Does anything open or close (EGR, IAC, etc.)? Are there any relays that might cause this? Advance says there's an EGR Valve position sensor on my car. I've never heard of this?
Thanks for any help!
