I have a 2002 CHEVY, malibu. Just had the Heads replaced, now I drove it and it seemed normal no sounds, I didn't feel a pull while I stepped on the gas pedal. This morning I turned it on (warm it up) it shut itself off. I drove it 4blocks from my home andI came to Stop and it shut itself off while in DRIVE. I put it in PARK it started up, drove normal, can you Please Help me out?