ok i was kinda thinking about this today regarding my idle surging, overheating at idle, and a weird sound coming from the iacv. so since this all kinda happened at once i figured they might be connected. so my questions is...if i had an air pocket in the line wouldnt that air pocket keep circulating with my coolant until it gets to the hightest point of the circuit...? in my case the highest point would be the top of my intake manifold right at the back where my iacv is located. would this make sense...im just trying to find answers to all my problems. im thinking that pocket is sitting there and its not allowing any coolant to get past because there is so much pressure being built up. maybe im on crack but i could kind of see this happening since i have taken off my TB and IACV like a million times in the last 2 weeks and havnt bled the system yet. im heading out right now to do it. thanks

 

did bleeding the system help or does it still over heat?

 

im just in the middle of it right now. im going to let my car get up to temp first...wait till the fans kick in.

also, how hard are you upper and lower rad hoses? i have never really noticed this before but they are both ROCK hard. serioulsly im scared they are going to burst...even though the engine temp is at the middle i cant even touch the valve cover....

ill get back to you about the bleeding

 

My idle surges alot too.... never used to...

I replaced my IAC and it still does it....
what else could it be?

 

rad cap possibly? that is my next thing to do. there was ALOT of air in my system so im going to do take if for a drive. the idle was steady at idle though but my idle is set at 750 right now.

 

Its a brand new cap

 

bleed your coolant system. this is what i did:

1. let the temp get to operating...just waited until the lower rad hose got warm that way i knew that thermstat opened.

2. opened up that bleed valve...right away a bunch of coolant came out so have something to catch it. it only sprayed a few inches. my upper rad hose was also insanly hot and pressurized so i figured there was no flow because of some air bubbles.

3. kept the bleed valve open until it the cup filled up and then closed the valve and dumped the cup into the overflow.

4. opened the valve back up and let it dribble out very slowly. it sometimes stopped for about 30 seconds and then coolant came back out so im guessing those were my air pockets.

5. repeated the opening and closing of valve until the dribbling stoppped. this took about 1/2 hour. make sure that you have coolant in your overflow because when the coolant system is down it will acutally suck some out of the over...so i read.

 

just have the front of the car in the air.

Then, connect a hose from the bleeder valve to the over flow, let car run and spit air.

 

what do you mean...just have the rad cap off and let it run for a while, while bleeding that valve back into the overflow?