I was on my way to work tonight. I was slowing down at a redlight and right when I got stopped my truck reved for a split second and the my speedo went to 70. This happened for just a split second. Has anyone experianced this? It was fine after it happened no CEL's no nothing. Just a quick blip of the throttle and the speedo issue.

 

might want to have your battery "load tested" and have the alternator checked as well.....check all grounds. Was it raining or snowing recently or during this "blip" of the speedo?? & any other gauges involved?

 

sounds like a loose wire. Check connections including the main red wire on the back of the alternator.