I recently replaced the 181K mile valve-burned engine in my 2001 Honda CR-V with a 40K mile engine from Japan. Since the swap idle is slightly erratic, acceleration from a stop is sluggish and check engine light indicates “P1508 error code” which is “Idle Air Control valve circuit failure.” Also have an issue with the A/C cycling on and off rapidly when idling that goes away as soon as the engine rpm is slightly increased. New OEM IAC valve is around $360 so I hesitate to replace it without informed opinions from the Car Talk oracle. All parts other than the engine itself are from my original engine in my CR-V. Any and all assistance is greatly appreciated.
The next time the idle acts erratic, take the handle of a screwdriver and rap on the IAC valve. If this causes the engine idle speed to change, then more than likely there’s a problem with the IAC valve. Have you checked the prices for an IAC valve from a local parts supplier?
Thanks very much for the feedback. Local dealership wants around $360 and local Napa dealer wants around $200. I think it may be a bit less from an online warehouse, but any suggestions you would like to put forth are, as always appreciated.
Its a circuit failure code which could indicate an IAC valve issue - or just a wiring problem. Having had an engine swap done it would be no surprise if a wire or connector was damaged / dirty, etc. Did you at least pull the IAC plug, clean & inspect and plug it all back up?