Sunfire L4-144 2.4L DOHC VIN T SFI (2001)
EVAP Control System Overview
The Evaporative Emission (EVAP) system uses a Fuel Tank Pressure (FTP) sensor, located on top of the fuel tank sender unit, in order to detect when
the EVAP system is purging. The fuel tank pressure sensor detects the flow from the engine through the EVAP canister purge valve. When the EVAP
system is not purging, the fuel tank pressure sensor will detect no change in the fuel tank vacuum. When the EVAP system is purging, the sensor will
detect a vacuum in the fuel tank. A change in pressure will be displayed on the scan tool. If a leak, an obstruction, or a malfunctioning sensor are present,
one of the following DTCs will set:
^
P0440
^
P0442
^
P0446
^
P0452
^
P0453
^
P1441
