what cause my car to keep defaulting to reduced engine power

When I had a "reduced engine power" message on my 2008 Impala SS, I ended up replacing the Accelerator Position Sensor. It is a 5 to 10 minute job (remove 2 bolts, unplug sensor, replace, then reinstall). The part cost about 80 dollars at AutoZone. The dealer wanted to charge almost 600 dollars to repair/replace this to address the issue (reduced engine power). Take a look at the video for more info on the part. http://www.youtube.com/watch?v=_hP4nGkG2bs This took care of my Reduced Engine Power issue.

your fly by wire system has a fault. you need a shop to check it before it stops entirely and leaves you on the side of the raod. Roy