General Information
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
Checking output signals from FTPS under detecting condition, if the FTPS indicates pressure momentarily increased more than 5.6 reading displaying on scantool, ECM sets P0454. MIL (Malfunction Indication Lamp) turns on when the malfunction lasts till consecutive 2 driving cycle.
DTC Detecting Condition
Specification
Diagnostic Circuit Diagram
Signal Waveform & Data
Fig.1) Normal waveform of FTPS at idle.
Fig.2) Normal data of FTPS at idle.