I believe I resolved a surging problem I had during closed-loop operation.

I was having a real problem with cruise-control in all gears except 6th due to this surge problem. Basically, the engine would add and pull the throttle back over and over again, making the ride unbearable. I even had a lot of missing and other anomalies during steady throttle driving.

I discovered a hose was loose that broke the close-intake hose routing behind the Mass-Air-Flow sensor. Once I put the hose back on tight, the problem cleared and the car runs very smooth now.

I was actually troubleshooting a loud deceleration noise that sounded alot like a bearing in either the idler or the SC. Lucky me it was just a loose hose.

(This is on an 8# ATI with twin Intercoolers.)