engine idle, low to high while stopped??
 

I have a 2006 Porsche Cayenne titanium edition. I just had the $2000 coolant pipe issue repaired on the vehicle. I picked the car up and when I parked at home I've noticed the following issue:

the idle continues to flip back and forth between high and low : 600 RPMs up to almost 2000 back down to 600. here's a link to a video of my cayenne doing this:


Does anyone have any thoughts? Intake not properly reinstalled?

This is a different issue than the coils, right?

Answered this on one of the other forums you posted it on..

Take it BACK. They fooked up something doing the pipes.

I am having this problem (i.e., Idling high and loud hissing noise when I'm not pressing the gas pedal). I just had the coolant pipe upgrade done on 2006 Cayenne Titanium.

What could be the problem? I will go back to the mechanic that did the upgrade, but I want to be sure what the problem is. This mechanic will most likely try to avoid taking responsibility for the issue.