This is bc there is 2 different GM 3 bar map sensors/part numbers. There is also a GM 2.5 bar. If you get one of the map sensors that are not preset in your software you can easily figure the scalar/offset.

1. You need minimum and maximum voltage and absolute pressures.
2. Convert the pressures to mbar.
3. Subtract the minimum and maximum voltages to find the range, then do the same for the pressures.
4. Divide the pressure range by the voltage range to calculate the scalar.
5. Multiply the minimum voltage by the scalar to calculate the offset. Note that a positive voltage gives a negative offset.

Just a little FYi