Fuel Tank Pressure Sensor (FTPS)
The Evaporative Emission Control System (EVAP) prevents hydrocarbon vapors from escaping from the fuel tank into the atmosphere where they could form photochemical smog. Gasoline vapors are collected in the charcoal canister. The Fuel Tank Pressure Sensor (FTPS) is an integral part of the evaporative monitoring system. The Engine Control Module (ECM) monitors the FTPS signal to detect vacuum decay and excess vacuum. The FTPS measures the difference between the air pressure inside the fuel tank and outside air pressure to check the purge control solenoid valve operation and for leak detection in the EVAP by monitoring pressure and vacuum levels in the fuel tank during the purge control solenoid valve operating cycles.