1999 Chevy Suburban Evap sensor getting code P0452

Evaporative Emission Control System Pressure Sensor Low Input indicates a low voltage problem in the Fuel Tank Pressure Sensor (FTPS). What the fuel FTP sensor does is convert fuel tank absolute pressure into electrical signals and inputs the signal to the ECM/PCM, (Computer).

First thing to do is make sure the gas cap is good and tightened properly. Then check the vacuum lines and wiring at the FTPS (Location-Fuel Tank) to be sure they are good, clean and tight.

Barring a wiring problem it can be a bad FTPS or PCM.