1992 GMC 1500 p/u, auto, 4.3 . 2 wd. 200k+ miles. Speedometer shows readings like a tach. no throttle shows 0mph, any throttle movement causes a reading from 22mph to 35mph to 70mph. Acts as if some 4 step voltage is bleeding over. I have installed new vss, instrument cluster, and tried new ecm. no change! I have unplugged vss at trans and still getting speedo and odometer readings. Can't figure it out! I think it has to be a voltage straying from speed buffer, tps, or some tach voltage but not sure. Any thoughts greatly appreciated. OUT OF IDEALS!
Feb 14, 2007 at 6:54 PM