Continuing idle problems...

[s1ngletracker]

I have a basically stock 93 tsi, other than an axleback exhaust, which is why this problem is so pronounced and noticeable. Stock boost, all emissions equipment still intact.

I just did a boost leak, eliminated a few leaks (other than one that appears to be ON the compressor housing). I blocked the FIAV, I just replaced my ISC with a known good one. TPS tested and looked good. Throttle switch also tested and checked out. Looked at the caps in the ECU, no leaks at all. New paper air filter.

2 things: When I am rolling out of gear, the idle lopes, between about 1100 RPM and 1500, bounces back and forth about once every second or two. When I come to a full stop, it will slowly settle to about 1100 RPM. So that's interesting.

Also, the idle is just a bit rough, not really smooth and steady. This becomes very obvious with the louder exhaust.

Any suggestions for what to look at next?