engine misfire

today my 99 tahoe,old body style,developed a problem i believe to be a bad ground somewhere.its been raining alot here , i live on a gravel road full of potholes which i believe caused the problem.every hole or bump i hit the headlights flicker/turn off,the left turn signal indicator lights...

I just bought a new 2009 Chevrolet Tahoe LTZ 5.3L 2WD 6-speed auto. I've put a little over 500 miles on it. On Monday of this week I went to start the vehicle and it turned over, but the entire vehicle started shaking side to side and the tact was jumping all over the place as well as the oil...