I've an issue on my 98 B18 civic. It's idling at 3k, but only once it's warmed up, and I've checked & cleaned the IACV, joined the coolant lines on the IACV & put a plate inbetween it and the IM but left it plugged in to bypass it. I've checked all vac lines, all fine. I've sprayed around the TB-IM and IM-head gaskets, nothing. Basically I've done everything I can think of. I'm open to suggestions, I'm quickly killing my clutch at lights & in traffic.Cheers
Dan.

 

Is the CEL ON?

Check whether the throttle cable is adjusted too tight and whether the throttle plate is stuck open.

 

No CEL, the cable was fine, but the plate was stuck open slightly, cheers for the suggestion, it's what my dad went for too. There I was with the IACV in bits, again, and messing about with coolant lines & bypasses, and I took the thermostat out too to give me longer before the symptom occurred.

When I got the Skunk2 TB there was a blue compund on the plate and on some of the venturi, I thought this was to help it shut properly, I was wrong, after a little while (the 1000ish miles it's done) the muck had got in and stuck to the blue compound, stopping the plate closing all the way. Cleaned the muck & other stuff off, it still lets a little light through, but nothing I can't live with, and now idles at about 1400, which I'm satisfied about for now, 800 would be better, but this TB is 70mm so it needs a map. If only my OBD2A power FC worked on an OBD1 car I'd be laughing, as is I need to find a UK neptune tuner, and quickly, as I'm probably running lean.