The evaporative emission control system 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 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 evaporative emission control system by monitoring pressure and vacuum levels in the fuel tank during the purge control solenoid valve operating cycles.
Checking output signals of fuel tank pressure sensor under detecting condition, if the tank pressure is lower than threshold, ECM sets P0452.
Item
Detecting Condition
Possible cause
DTC Strategy
Signal check, low
Poor connection
Open in Power Circuit
Open or short to ground in signal Cirucit
Faulty FTPS
Faulty ECM
Enable Conditions
Engine speed > 500rpm
Threshold value
FTPS Voltage < 0.24V(-3.9 kPa)
Diagnosis Time
Continuous
MIL On Condition
2 driving cycles
Pressure (kPa)
Output Voltage (V)
-6.67 (26.7VAC)
0.5
0
2.5
6.67 (-26.7VAC)
4.5