two of us have this problem. both developed at the same time (weird):
when i start my car (cold) it idles at 2000-2500rpm. it dips to 1800, then up, 1800, then up. i've replaced all my vacuum lines, so WTF?
the car USED to start up at 1500rpm, stay steady, drop to 1000 (per hondata tune) and be cool.
my buddies car does the SAME THING.
mine also has the following problem:
after warming up, i shut the car off..and when i restart it, it idles at about 600rpm and acts like it wants to die. it has, twice. after running a bit, or driving, it's cool. it is something in the "startup" programming of my ECU + the 550 RCs? i ask, 'cause when i start the cary i THINK i can hear the injectors dumping a grip of fuel.
i'm stumped. anyone got an idea? i ran a search, but i couldn't find anyone with the exact same problems.
maybe a sensor/check valve/etc/???

 

if your car is obd0 or obd1 check your fitv

 

obd1, and not to sound like a noob, but which is the fitv? i'll check my helms in the meantime. thanks, yo!

 

Under yrou throttle body. There is a valve, that opens when cold closes when hot. It's what makes your car idle at 1500 cold and 800 hot. Sometimes they need to be replaced. More times than not you can just take off your throttle body. Take that valve apart and re-screw it back in. It's very easy to do. I've had it happen a couple times to different cars. Souds exacty like the symptoms to me though.

 

saweet. i'm all over it. first thing tomorrow after work. thanks.

worse comes to worse, i have two others i can switch out.