General Information

Component Location





General Description

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.

DTC Description

The Tank Pressure Sensor Stuck Diagnostic continuously monitors the fuel tank pressure sensor output for a stuck condition. It does this by comparing the maximum and minimum raw tank pressure voltages. If the difference between the two values exceeds a threshold, then the diagnostic is considered to have passed. The diagnostic is not allowed to fail unless (a) a significant portion of the EVPD (Evaporative Diagnostics) tank draw has occurred or (b) the tank pressure has not changed after purge transitions off from a flow level high enough to cause a change in the tank pressure.
Checking output signals of tank pressure under detecting condition, if the tank pressure difference between maximum and minimum is low than 0.9996 for 60 secs, PCM sets P0451 MIL (Malfunction Indication Lamp) turns on when the malfunction lasts till consecutive 2 driving cycle.

DTC Detecting Condition





Specification





Schematic Diagram