MountainDont
Newbie
My C1500 has OBD-II, so I immediately checked the speed on it. It's correct. The gauge reads 18% higher than reality.
I have a newer Chevy that has a notoriously bad speedometer (Chevy Trailblazer) and fuel gauge. (Those vehicles often need a cluster refurb or replacement, but their symptoms are different... they often just stop working altogether.)
Anyway, my 1998 C1500 has this:
1. The cluster's tachometer reads a little higher than the digital one
2. The cluster's speedometer reads about 10 mph faster at 55 mph (it says 65)
3. The gas gauge reads a bit lower than it's supposed to, even accounting for the engineering trick that shows you less fuel than you actually have at low fuel levels and extra fuel when nearly full.
Are these repairable? Like using stepper motors? (i.e. steppor motors when misspelled)
As a side note, my truck is said to have a "VEHICLE SPEED SENSOR CALIBRATOR MODULE" (VSSCM) according to the service manual, but I have not seen anyone ever messing with these. It is supposed to be behind the glovebox. The problem is that these control the vehicle speed (VSS) that can be read from OBD-II.
In other words, if I mess with the VSSCM, it will change the VCM to output a bad VSS that is currently correct on my vehicle, as I have the stock wheels and rear-end.
As a side note, I would think that re-calibrating over OBD-II and a scanner would change the correct reading of the speedometer to the wrong value -- the VSS would be wrong as before. And I am pretty sure you can't mess with the other two anyway.
I have a newer Chevy that has a notoriously bad speedometer (Chevy Trailblazer) and fuel gauge. (Those vehicles often need a cluster refurb or replacement, but their symptoms are different... they often just stop working altogether.)
Anyway, my 1998 C1500 has this:
1. The cluster's tachometer reads a little higher than the digital one
2. The cluster's speedometer reads about 10 mph faster at 55 mph (it says 65)
3. The gas gauge reads a bit lower than it's supposed to, even accounting for the engineering trick that shows you less fuel than you actually have at low fuel levels and extra fuel when nearly full.
Are these repairable? Like using stepper motors? (i.e. steppor motors when misspelled)
As a side note, my truck is said to have a "VEHICLE SPEED SENSOR CALIBRATOR MODULE" (VSSCM) according to the service manual, but I have not seen anyone ever messing with these. It is supposed to be behind the glovebox. The problem is that these control the vehicle speed (VSS) that can be read from OBD-II.
In other words, if I mess with the VSSCM, it will change the VCM to output a bad VSS that is currently correct on my vehicle, as I have the stock wheels and rear-end.
As a side note, I would think that re-calibrating over OBD-II and a scanner would change the correct reading of the speedometer to the wrong value -- the VSS would be wrong as before. And I am pretty sure you can't mess with the other two anyway.
