MAP sensor voltage?

[MA2LA]

I'm having some issues with my commander giving odd boost numbers and I'm not sure if its the commander or the MAP sensor. I though that with the key on and the motor not running I should have 5 volts but I am getting 1. 3 and the gauge is reading 8psi. Its odd that the ECM hasn't thrown a code for high boost considering it has shown 45psi with I know is not accurate all so I'm confused.

 

[rbattelle]

This may sound silly, but are you sure you're reading the MAP sensor and not the IAT sensor?

MAP sensor should be on the downstream side of the turbo compressor.

Ryan

 

[Little Bill]

The MAP sensor is calibrated for absolute pressure. It should have an output of 1 volt at sea level. 1. 3 volts should give a gauge reading of 4. 4 psi. Power to the sensor is 5 volts.

 

[MA2LA]

hummm I wonder if i'm getting 5 volts to it. an yes it is the MAP sensor. I guess i'll check everything out again and proble go buy a sensor. I'm just wondering what the smarty jr is thinking when it sees 48psi and how much fuel is it trying to dump.

 

[betterthanstock]

Gage pressure is absolute pressure minus 14. 7 psi at sea level. So at 48 psi on the map sensor, it's really 48-15=33 psi gauge pressure.