Along the throttle hang lines, I'm experiencing it almost daily (posted last month). I'm looking for solutions if anyone is offering. It really makes the car undriveable when it's going on:
"I've had this problem ongoing with my SVT as long as I've owned it. The IAC valve and throttle body were replaced at 60K miles, but the problem resurfaced a few weeks back (77K miles now). Don't know if winter gas has something to do with it. I'd messed around with the TH fix a long while back, to no avail. In my case, you can actually feel the car pulling without touching the gas (like the cruise control is on). And then if you go to shift, the revs will actually rise up to 3500-4500 rpms and hang there up to 15 seconds before eventually (slowly) falling back down. You can tell when the problem will occur when the idle is ~1200 rpms at rest vs. ~750 rpms when the problem doesn't occur. Hopefully not something that is going to be as frequent a nuissance as it had been prior to the new t-body and IAC valve..."