jpacetti

Three months ago I got a ticket and the cop told me I was going 5 mph faster than I thought I was. About a month later my speedometer went haywire and worked only when it wanted to. I however bought a GPS and it seemed I was always going 5 mph faster than my speedometer says. This seem to fix the problem until 3 weeks ago the same problem came back. I replaced the speed sensor for the second time.

I spoke with the guys at MPS auto salvage where I bought my GT conversion kit and they said the fact that I hadn't swapped the rear end out yet was the contributing factor why there was and still is always a 5 mph difference. This makes a bit of sense cause I'm still pushing the V6 rear end which is pretty different than the V8.

I was driving it from GA to LA yesterday, and with the cruise control on on level ground I watched my speedometer move between 70 and 85 mph while my GPS stated I was only going 79 mph steady.

Both of the speed sensors I have bought were aftermarket sensors I got at Autozone. Is it possible that those sensors just don't hold up to long distance driving? Or is there a common problem that causes this? Could this be a wiring issue? Any help and advice is appreciated.

jpacetti

Bump - Anyone??

Shotgun Love

have you tried getting a speed cal or a tuner to reflash your ecu?

jpacetti

No I haven't since my problem arrised. I had it tuned and flashed after I installed the V8 last fall. Had to to get the car to run. I don't have a good wiring diagram... Does the ecu receive the signal before the speedometer? Or does the speedometer read directly from the speed sensor?