i have a 2000 ls with Idle issues similar to what has been posted. Between 14 and -31F degrees my cars idle wanders and eventually goes into a weird wander that reminds me of a rev limiter at 1500 rpm and the choke kicking of on a carberated car. Then it throws a PENDING code for IACV malfunction!!! So far i have replaced the IACV, bench tested the new IACV, checked TPS, checked IAT, replaced coolant temp sensor, replaced MAP, and checked all voltages from ecu. After all this i gave up, brought it to the only local acura dealership who spent two days and eventually gave up on it and suggested i try somwhere else, so i took it to Honda and they couldn't figure it out either after bringing my car there 2 times!!! If anybody has any suggestions it'd be great!!

 

bump

 

any ideas???

 

when the car is warmed up do the rpm's go back down? does it run normal after this?

 

mine did a very similiar thing and what was wrong with mine was i actually had the ground wire to the top of my thermostat housing lose... have you checked all your grounds?

 

on a side note, did acura and honda charge you to look at your car?

 

i havent look at the grounds but i know the ones ive seen could use replacing and no acura and honda did not charge me, they just were as frustrated as me that they couldn't figure it out