So I have a 91Lx Accord with a f22a6 swap from a 93 Ex accord (swap was done years ago by previous owners). Its my first project car and track build so I'm fairly new to all this so please bear with me. It's got a fluxuating idle from about 1500 to 2500 and it starts once it's warmed up for a few seconds after a cold start, before that it holds idle around 2000 or if its already warmed up it fluxuates as soon as I start it . Got a IACV from the junkyard and installed it but it didn't make a difference. I used a 5 finger discount so I can't exchange it either. Can anyone tell me what else it can be ? I know the idling system has multiple components so which other component can cause this ?

 

Surging idle causes are;
• IAC or FIT valve dirty or out of adjustment
• Vacuum leak, worn gaskets or cracked/disconnected vacuum hoses
• low coolant or air pocket in cooling system.

There is a good thread in the FAQ covering IAC and FIT valve cleaning and adjustment. Where this starts after the engine is warm I would check the FIT valve or ECT sensor.

 

Awesome thanks dude, I'm gonna rebuild my motor soon so ill look into all that so I can know what to look for, thanks again !