Diagnostic Trouble Code (Dtc) P1441 Evap System Flow During Non-Purge - Isuzu 1999 RODEO Workshop Manual

6E2–402
RODEO 6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) P1441 EVAP System Flow During Non-Purge

Legend
(1) Induction Air Control Valve
(2) Air Separator
(3) Solenoid Valve
(4) Canister
(5) Rear Side Member
(6) Radiator
(7) Throttle Body
(8) Solenoid Valve (Duty)
(9) PCV Valve
The evaporative system as defined by federal regulation
includes the following components:
f Fuel tank
f EVAP canister vent solenoid
f Fuel tank pressure sensor
f Fuel pipes and hoses
f Vapor lines
f Fuel cap
f Evaporative emission (EVAP) canister
f Purge lines
f EVAP canister purge solenoid
The EVAP purge solenoid valve allows manifold vacuum
to purge the canister. The Powertrain Control Module
(PCM) supplies a ground to energize the solenoid valve
(purge "ON"). The EVAP purge solenoid control is Pulse
(10) Front Side Member
(11) Vacuum Tank
(12) Check Valve
(13) Evapo Service Port
(14) Vacuum Switch Valve
(15) Fuel Pressure Control Valve
(16) Vacuum Tank
(17) Vacuum Switch Valve
(18) Induction Air Control Valve
Width Modulated (PWM), or turned "ON" and "OFF"
several times a second. The duty cycle (pulse width) is
determined by engine operating conditions including
load, throttle position, coolant temperature and ambient
temperature. The duty cycle is calculated by the PCM
and the output is commanded when the appropriate
conditions have been met.
The system checks for conditions that cause the EVAP
system to purge continuously by commanding the EVAP
vent solenoid "ON" and EVAP purge solenoid "OFF"
(EVAP vent solenoid "CLOSED," EVAP purge PWM
"0%"). If the fuel tank vacuum level increases during the
test, a continuous purge flow condition is indicated. This
can be caused by the following conditions:
f EVAP purge solenoid leaking
f EVAP purge and engine vacuum lines switched at the
EVAP purge solenoid
755RW028