auffy16

Hey guys,

Last week I took the evo out after leaving it sit for a couple weeks, and I noticed that at idle it jumps to 2k for a few seconds then returns to normal idle which is about 1k (I am also getting a slight smell of coolant, but no known leaks). At night I noticed that my instrument cluster would flicker randomly, so I'm wondering if anyone else has experienced this. I'm wondering if it is a water pump issue, or if it's an issue with the iacv, or both. Car has 42k on it.

Womb Raider

my evo does the same. In reference to it jumping to 2k.
everytime i start it cold it jumps up to just below 2k but starts droping to 1k after warming up. I thought it was normal. (32k miles)

auffy16

yeah, mine's doing it when warm..

Womb Raider

Sounds kinda like the iac. Had a problem that sounded like that with my car before the evo. Besides the coolant smell atleast. The cluster will start dimming when rpms get really low?

auffy16

It seems to do it intermittently, kind of like the idle surge. It could be an electrical issue maybe, maybe a relay. Doesn't seem many people have had this issue, so maybe it's a couple different problems.

4b11slayer

If your smelling coolant and your idle is surging i would say its because your coolant leak. If im not mistaken the iacv relies on coolant for idle. Check your coolant level.

Biggiesacks

Coolant leak is bad, you should check that out especially if its leaking from the throttle body onto the IAC, but the coolant circulating into the throttle body is to prevent it icing up and has nothing to do with actual IAC operation. What kind of condition is your battery in? Check/clean your battery terminals and check your chassis grounds in case they are loose.

auffy16

battery is less than a year old with very minimal corrosion. Guess I'll just have a test done to check for coolant leaks. Thanks guys!