Hey! Need some help as usual my duramax is having some strange electrical issues. I'll be driving under normal conditions not touching or changing anything when my radio shuts off, then my tuner, and then I will loose all my gauges except my speedometer and RPM. The security light, battery...

I recently installed this chip into my 2006 duramax, I wanted to get better MPG i was only getting 12 average which sucks really bad for this truck, I have only had chip a couple of days about how long till i actually start seeing results on better MPG, and has any one encountered any problems...