P0441
Symptom: CHECK ENGINE lamp (MIL) on.
EVAP canister purge valve, low flow
Fault symptoms
CHECK ENGINE lamp (MIL) on.
Conditions
P0441
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Diagnosis not yet performed this
trip.
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Engine coolant temperature >
60°C.
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>18 minutes since engine
started.
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Diagnostic help
The diagnostic trouble code indicates that a flow exists even though the purge valve is
closed.
Whether air or fuel vapour is sucked through the valve makes no difference.
Diagnosis of the EVAP canister purge valve can be activated with the ISAT scan
tool.
On completion of diagnosis the ISAT scan tool will show "READY", otherwise
"NOT READY".
The EVAP canister purge valve can be activated by means of the ISAT scan
tool.
Check the wiring
Intermittent faults may occur as a result of temporary short circuits and breaks in the
wiring. Jiggle the wiring at several points and in different directions to ascertain whether the
wiring harness, including any connectors, is causing the trouble. Observe the multimeter,
ISAT scan tool or test lamp while doing this.
Diagnostic procedure
1. Check the air flow
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Unplug the purge valve's 2-
pin connector.
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Disconnect the hose from the evaporative emission canister side of the
valve.
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Start the engine and, by means of the pressure gauge on the pressure/vacuum
pump, check whether air is sucked into the valve.
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Is air sucked into the valve?
Change the valve. Continue with point 4.
Continue with point 2.
2. Check the valve
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Switch off the engine and plug in
the purge valve's 2-pin connector.
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Start the engine and run it until the
temperature of the coolant exceeds 60°C (140°F), or for at least one minute if this
temperature is reached earlier.
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Check that air is sucked into the valve in pulses.
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Is the valve pulsing?
Continue with point 3.
Change the valve. Continue with point 5.
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Note
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The valve is active/inactive at varying
intervals.
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3. Check the purge flow from the evaporative emission
canister
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Connect the vacuum pump to the
hose from the evaporative emission canister.
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Check whether a steady purge flow is obtained from the evaporative emission
canister.
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Is a steady flow obtained?
Change the purge valve. Continue with point 5.
Repair or replace the hose and also change the evaporative emission canister,
if necessary. Continue with point 5.
4. Check the valve's power supply
Unplug the connector from the EVAP canister purge valve.
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Connect the test lamp
to:
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Turn the ignition switch to the ON
position.
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The test lamp should light up.
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Connect the test lamp
to:
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Start the engine and run it at idling speed.
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The test lamp should light up or start flashing.
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Note
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The valve is active/inactive at varying intervals.
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Test lamp on as above?
Change the valve.
Continue with point 5.
Check the wiring connected to the control module for continuity and
shorting.
Rectify any faults. Continue with point 5.
5. Final check
The ISAT scan tool is used to activate diagnosis of the EVAP emission system.
For diagnosis to be possible, the following conditions must be fulfilled:
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Engine running at idling
speed.
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Vehicle speed = 0 km/h.
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Perform diagnosis:
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Connect the ISAT Scan
Tool.
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Select "EVAP
DIAGNOSIS".
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Wait for about 2 minutes or until the ISAT scan tool reads
"READY".
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Obtain a readout of the diagnostic trouble code.
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Has the diagnostic trouble code recurred?
Continue as described in
.
The steps taken to rectify the fault were correct.
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Important
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Fault diagnosis can be stopped if evaporation of petrol is excessive or if the evaporative
emission canister is saturated. To continue diagnosis, proceed as
follows:
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