Opening it up, the car falls on its face!

Well when i floor my car it falls on its face. It doesn't do it all the time. This is what happens when it falls on its face.

All the gauges in the car look like they are going back to zero. They go back up when i let off. When i let off and drive slow the car if fine. Sometimes when i hit a bump on the street it falls on its faces.

I was thinking it maybe a ground wire messed up, what do you guys think? Do you guys have any idea what it can be?? Does anyone know where the ground wires are at on a 96 GT or a 99 Cobra??? I ask on both cars because for those that don't know i have a 99 4v in my 96 gt. Ok thanx guys.
 
DBMSTNG said:
you are probably running lean and meesing up the spark plugs and sensors.

I just put in new spark plugs, and as for the mass air sensors its fine. We cleaned the MAS too. The car is not running lean.

Its either the ground or the o2 sensors. Doesn't hurt to check them out when i'm under the car. Hmm but what do the o2 senors have to do with my car losing power in the gauges cluster.