The evaporative emission
control system prevents hydrocarbon (HC) vapors from the fuel tank from
escaping into the atmosphere where they could form photochemical smog.
Gasoline vapors are collected in the charcoal canister. The PCM controls
the Purge Control Solenoid Valve (PCSV) to purge any collected vapors from
the canister back to the engine for combustion. This valve is actuated by
the purge control signal from the PCM and controls fuel vapor flow from
the canister to the intake manifold.
Checking output signals
from fuel tank pressure sensor under evap.system test, if fuel tank's
vacuum is higher than prescribed threshold, PCM sets P0441.
Item
|
Detecting
Condition
|
Possible cause
|
DTC
Strategy
|
| •
|
Monitor the fuel tank's
vacuum | |
|
EnableConditions
|
| •
|
10 V < Battery voltage < 16
V |
| •
|
Barometric pressure > 72 kPa (0.72
bar) |
| •
|
Engine coolant temperature at startup -
Intake air temperature at startup < 6.7°C(12
°F) |
| •
|
Engine coolant temperature at startup:
4.5 ~ 35°C(40 ~ 95 °F) |
| •
|
Intake air temperature at startup: 4.5 ~
35°C(40 ~ 95 °F) |
|
Threshold
value
|
| •
|
Fuel tank's vacuum > a prescribed
threshold | |
DiagnosisTime
|
| •
|
One time during Evaporative system
diagnosis | |
MIL On
Condition
|
|
|
Evaporative Emissions Systems (EVAP) Leak
Tests can be run by the Scan Tool. |
| 1. |
Install scan tool and IG "ON" and then clear
DTC. |
| 2. |
Select and press "EVAP.LEAKAGE TEST" mode in
the scan tool. |
| 3. |
Check if the vehicle is under test conditions
as below [Fig 1]. |
| 4. |
If OK, Start engine and restart Evap.Leakage
Test again[Fig 2].
|
| 5. |
Is the same DTC set after the Evap.leakage
test with scan tool ?
|
|
▶ Go to
"Component Inspection" procedure.
|
|
|
▶ Fault is
intermittent, go to "Verification of vehicle Repair"
procedure.
|
|
| 1. |
Check PCSV for leakage
| (2) |
Disconnect the hose leading from the
PCSV to the intake manifold at
PCSV. |
| (3) |
Apply a vacuum at the nipple and verify
that the PCSV holds vacuum. |
| (4) |
IG "ON" and perform ACTUATION TEST for
PCSV with scantool(should hear a faint click from
PCSV) |
| (5) |
Vacuum should be
released. |
| (6) |
Repeat this procedure 4 or 5 times to
ensure PCSV reliability. |
| (7) |
Is the PCSV working
properly?
|
|
▶ It
was intermittent failure., go to "Verification of
Vehicle Repair" procedure.
|
|
|
▶
Substitute with a known - good PCSV and check for proper
operation.
▶ If the problem
is corrected, go to "Verification of Vehicle Repair"
procedure.
|
| |
| Verification Of Vehicle
Repair |
After a repair, it is
essential to verify that the fault has been corrected.
| 1. |
Connect scantool and select "DTC"
button. |
| 2. |
Press "DTC Status" button and confirm that
"DTC Readiness Flag" indicates "Completed". If not, drive the
vehicle within conditions noted in the freeze frame data or enable
conditions |
| 3. |
Read "DTC Status"
parameter |
| 4. |
Is parameter displayed "History(Not Present)
fault"?
|
|
▶ System
performing to specification at this time. Clear the
DTC
|
|
|
▶ Go to the
applicable troubleshooting
procedure.
|
|
