2011 CHEVROLET SILVERADO 1500 Engine And Engine Cooling Problems

Vehicle door locks activate lock and unlock while simultaneously downshifting the transmission, the engine dies, the dash cluster stops working, engine starts again, dash cluster begins working again. After this occurs, when the vehicle is shut off, there is a loud "pop" sound heard over the speakers and no interior lights. The vehicle may or may not have any cab power. Cycling the ignition provides little to no help. After the vehicle sits for a while, it may or may not start again. The vehicle stereo will randomly change from FM to aux. The a/c panel will flicker and the blower motor will fluctuate. This can also be seen while watching the battery gage on the instrument cluster. It will go from around 14 volts DC to around 9 volts DC and back up again.

THIS IS A DEALER DEMO VEHICLE, FIRST 2235 MILES WERE DEMO. DURING MY FIRST MORNING (12HOURS AFTER PICKING UP AT DEALER) OF OWNERSHIP I WAS DESCENDING DOWN A HILL WITH THE CRUISE ON, AND THE VEHICLE PROCEEDED TO OVER SPEED APPROXIMATELY 5-7MPH. I TRAVEL THIS HILL BOTH WAYS TO/FROM WORK DAILY AND THIS HAPPENS EVERYTIME. I THOUGH THIS MIGHT BE AN ABNORMAL ADJUSTMENT WITHIN THE COMPUTER/ETC SO WHILE TAKING IN TO THE DEALER FOR A TPMS (TIRE PRESSURE MONITOR SYSTEM) ISSUE I MENTIONED THE OVERSPEED ISSUE TO THE SERVICE WRITE UP AND THEY SAID THAT IT WAS NORMAL. I DON'T AGREE, BUT MAYBE IT IS. IT DOES ADJUST BACK TO NORMAL CRUISE SET SPEED BUT IS UNIQUE. I HAD A 2002 DODGE RAM 1500 PREVIOUSLY AND IT DID NOT DO THIS, AND I HAVE DROVE OTR (OVER THE ROAD) SEMI-TRUCKS AND KNOW THE DIFFERENCE WITH OVERSPEED BEING NORMAL AND ABNORMAL....