5.3 j code in vin.
This vehicle will accelerate own its own from a dead stop in fprward or reverse. Just take
foot off brake on level ground and starts rolling, then in 20 or so feet, it accelerates from 900
rpm to 1500 and does this as if you push throttle, but not touching at all. My mechanic is
baffeled as well. Any thoughts or seen this behavior before? Thanks