IAC.... how hot is yours????

[budwich]

I have changed out my IAC a while ago (8 months) with a "non-name" ( ie. NAPA part) because of the "moose" problem.... that problem has gone away..... not good especially during hunting season... Anyways, the idle seems to be high (800-900) even after throttle body cleaning, linkage lub, etc. I have disconnected the battery for reset a couple times with no change.

One thing that I noticed from my old IAC and the new one is that they seem to be very hot... almost to the point of not being able to touch the motor body of the IAC.
I was wondering if this is an indication of a problem ( low resistance... too much current, too much heat) or if these things run that hot. Recently, I have had idle surges when I go to hit the brake at an intersection, the truck speeds up to 1500plus rpm... almost scary.....and actually releasing the brake appears to cause an RPM drop back to 800-900. I have seen a couple posts about this being an IAC problem but I have trouble believing that the replacement is bad already. So how hot is your IAC????

One other thing that I have tried per some postings is disconnecting it, the idle then goes down to around ~600 which seems about right.

 

[BrooklynBay]

Have you checked all of the vacuum lines? Sometimes a break in one of them could cause the idle to jump. Does the IAC seem a lot hotter than any other part under the hood? Check the air filter, throttle body, and MAF for any restrictions, or dirt build up. It's possible that you are not getting a sufficient flow of air going into the IAC. The lack of air flow could make it feel very hot, and cause driveability problems like erratic idle flares, stalling, hard starting (similar symptoms to a broken vacuum line).

 

[Brandons]

My iac usually sticks as hot as the intake or a bit cooler. Maybe return the party, probaby some warrenty?

 

[budwich]

It appears that the surging problem has been resolved with a replacement of the TPS. It still appears to idle high but I haven't disconnected the battery since I installed the TPS so I will give that a try for a reset on "running conditions".

 

[Lazzman]

Removed my IAC a few weeks back after a 40min highway ride home from work. Summer weather air temp around 82.

When I got home the new IAC gasket had arrived so I wanted to put it in pronto. The truck had sat for about 25 minutes. The IAC was very hot actually to hot to hold and actually burned my hand, no damage just pain.

It also got me to thinking why this was to hot. Had to be over 200 degrees, like a hot potato in my hands.

Sits on top of the plastic manifold, it should not be that hot.

What exactly does the IAC do? I know there is an eletric motor that lets air in but how does this process work? If the motor were left open for a long time it would get hot.

I do believe my vehicle has a vacum or gasket leak and has trouble getting required air into the engine.

 

[budwich]

Wow... that's hot. I wasn't expecting a servo motor type device to be that hot so I don't know why. From what I gather, the vavle operates on idle but also when your cruising down the road and take your foot off the gas, the valve opens up to provide air to prevent over rich / stalling. But I can't believe that a motor running that hot is good in the long term. Anyways, both my new IAC and the old were pretty hot and it seems your was also so maybe its "normal". I thought perhaps it was a symptom that it was going bad or was bad.