poor/low idle when warm
 

when my 96 civic is up to operating temperature, for some reason it wants to idle around 500 RPM's and sometimes just falls down like its gonna die and then shoots back up over 1k and then back down to around 750rpms. Its really weird im thinking maybe the MAF sensor or something. Its got a tenzo R intake, dc sport header, apexi catback.

any help would be appreciated.

Is the CEL ON?

Some things that can cause a hunting idle problem:

-Dirty IAVC (see forum DIY section for cleaning instructions).

-Air trapped in the cooling system. Top off the coolant level in the radiator and bleed the system of air.

-An intake air or vacuum leak. Check hoses and connections leading to the intake manifold.

i will check those things out. But the CEL has been on and off for the past year ive had it. But just within the last month or 2 the idle problem has come up.

Could be the IACV, i'd go clean it.. Or, better yet. Go give your car a nice Seafoam treatment and see if that helps any. I'd also reccomend taking your car to autozone and see what codes are being pulled by the CEL, so you have a basic idea where to go from.

+1

The CEL code can also be pulled at home (see link in my signature).