OK....so in my last thread I was having idle problems, ended up swapping the IAC from our 00 Burban into my truck, and the idle problems moved from my truck to the Burban. Problem solved, or so I thought...

After a 25 minute drive on the freeway, I pull up to a light and the truck wont drop below 1200 rpm in gear when I come to a complete stop. I put it in neutral to see what the hell is going on, and it jumps up to 2300 or so. I figure the "new" IAC is stuck wide open, so I have to push the truck into a parking lot to take a look.

I ended up moving the IAC valve / stopper thing around manually until I got the truck to idle just under 1000, then unplugged the harness from it to keep it from moving again.

Now...that's two IAC's that are dead in two days. What the hell is causing this??? The IAC from the Suburban lasted all of 25 miles. Very frustrated!! Any ideas???

 

Have you ever ran a DMM to it to see what kind of voltage your getting through it, maybe something in your system is causing it to over power your IAC, causing it to short out? just a theory

 

No but I can...what are the voltages supposed to be?

 

I'm actually not sure, not really a GM expert, but i would since anywhere from 12-12.6 volts, or 5volts

 

Well it wasn't that exactly, but you were on the right track. On the Radix the wire loom for the idle air control and for the throttle position sensor pass right under the EGR hose. Somewhere along the line the wire loom touched the EGR hose and melted to it, and a couple of the wires had their insulation melted off and were shorting out together. The IAC module is working perfectly, patched up the loom and routed it over the nose of the supercharger instead of under, so it looks like the short was the cause.

 

it definately sounded like something was shorting it out, and well that definately would do it....

well to fixing the problem, thats why its hard to fix things over the internet because u cant poke around an engine bay and test things haha, but good job fixing it, hope it stays fixed.

 

Oops...I guess it was that exactly. I didn't re-read your post. You nailed it, thanks! I hope it stays fixed too.