i have taken my card to multiple mechanics. local honda dealership will not service my car or even look at it, says its too old. the check engine light keeps coming on and its because the Idle Air Control Valve. when car starts it revs up to 2000 rpms then drops. this part has been replaced 2 or 3 times and still same issue. new mechanic suggests replacing with OEM part not a knock off. any ideas or suggestions would be greatly appreciated.

 

It is not uncommon to experience engine surging (a.k.a., "idle hunting", "throttle pulsing", the phenomenon goes by many names...) subsequent to the completion of some maintenance work that affects, believe it or not, coolant! The IACV lives at the topmost part of the coolant circuit (under the throttle body on '00 3.0L VTEC V6 engine). If an air pocket forms within the IACV body, the thing will malfunction, which manifests as engine surging and usually without lighting the Check Engine Lamp. The simple test: Perform a thorough and proper air purge of the coolant system BEFORE you suspect a bad IACV!

My suggestion is to follow the suggestion of the new mechanic: Purchase an OEM Idle Air Control Valve (a.k.a., "Rotary Air Control Valve Set") and not aftermarket. Optionally buy a used Genuine Honda IACV from a salvage yard (LKQ Parts and Beaver Honda offer shipping). I totally sympathize with the temptation to purchase an aftermarket IACV—a new genuine Honda IAVC is ouchy-expensive. But for some reason the ECU on this generation Accord does not play well with an aftermarket IACV, and the brief surge to high-rpm at engine start with subsequent drop to normal RPM is the classic symptom of this pairing. (BTW... mucho kudos to the mechanic with knowledge of this rather esoteric bit of information.) Now you know; and "two or three times" over should settle this fact in your mind.

A thought...
If you still have the OEM (and presumably genuine Honda) IACV in your possession, you might give it a thorough cleansing with some throttle cleaner and a bamboo skewer—these things tend to collect lots of carbon yuckiness. If, after reinstalling it and despite any attempted cleaning, your idle is still wonky, then heave a plaintive sigh and accept that the electronics within the IAVC are the culprit. It's certainly worth a shot in any case.

Swapping an IACV is well within the capability of a motivated guy with a socket set and the ability to follow instructions. A handful of videos on the YouTubes demonstrate the process.

Lastly...
Dealerships suck *****. Never ever take your car to a dealership. Take your Accord to a local, reputable Honda-centric shop instead.