Confused engine sensors

[at t 2d]

I just got my TTA a few weeks ago and it is definitely not running well. Not making any where near the power it should and idling very rough. I took it to a local 3.8 turbo guru and he plugged a scanner in to it. The manifold air temp, coolant temp, and volts are fluctuating wildly. We are thinking it is a grouding problem.

Any suggestions on where to start looking?

 

[Quiky One]

Had this issue with mine and it was a bad ECM. All my readings were erratic.

 

[WS6]

Has it thrown any codes? Fixing grounds is cheap to do, and worthwhile even if doesn't help your particular problem. If it(the ECM) is throwing a few codes over and over then It's probably the ECM like Jason says.

 

[at t 2d]

I was getting an intermittent "lean" code. Pontiac replaced the O2 sensor and it has not returned.

Any ideas where to start looking for a ground problem?

 

[WS6]

Any ideas where to start looking for a ground problem?

On the intake, towards the rear. Nearby the Trans dipstick tube.