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P0442

Read the instructions below then start the fault diagnostic procedure.

Symptom: CHECK ENGINE. Possible smell of petrol.

P0442


EVAP. Small Leakage in System.


Fault symptoms


• CHECK ENGINE.

• Possible smell of petrol.


On-Board Diagnostics

Type of diagnosis:


- Once per driving cycle. Interrupted when fault criteria fulfilled or OK reported. Restarts next driving cycle.


Enable criteria:


- Test 1: Coolant temperature at start between 5°C - 40°C. Purging active. Idling. Max. one change in status of brake light switch. Purging adaptation higher than -6%. Intake air pressure at least 25 kPa lower than the atmospheric pressure. The vehicle stationary for 5 sec. The diagnosis will start once the above conditions have been fulfilled. If the diagnosis is interrupted then the speed must exceed 0 on one occasion before it is allowed to restart. The diagnosis continues then as described in phases A-C: A) The shut-off valve is activated at the same time as the purging is stopped for 4.5 sec. In the meantime the tank pressure is observed. B) The purging valve's pulse ratio is set at 18% until the tank pressure drops by 0.6 kPa whereupon the purging is interrupted. The pressure drop must not take longer than 15 s. If the pressure drop occurs too quickly during this phase the diagnosis will be interrupted because there is too much fuel in the tank (more than 85%). C) The tank pressure is observed for max. 6 s.


Fault criteria:

If the pressure drops by more than -27.5 Pa/s in phase A, then an internal leak in the purging valve has been detected. If the pressure cannot be reduced to 0.6 kPa within 15 seconds in phase B then a major leak has been detected. If the pressure rises too quickly within 6 s in phase C then a small leak has been detected. Diagnostic trouble codes are generated when the fault criteria are fulfilled during the test and the dependants are OK. P0441 for faults during phase A. P0455 for faults during phase B. P0442 for faults during phase C.

Dependents:


- P0444, P0445, P0451, P0452, P0453, P0501, P0502, P0506, P0507, P1444, P1445, P1451, P1452, P1453, P1576, and P1577.


System reaction to a fault:

“TIGHTEN FUEL FILLER CAP” will be displayed on SID if a major leak occurs. DTC will then be P0455.


-


OK report:

Test performed once and fault criteria not fulfilled.

Fault handling: (See section “Fault diagnosis, general” for more information.)


- Type III.


Diagnostic help

Fault diagnosis concerns a leak.

Functions in the diagnostic tool related to the fault:


• Diagnostic status for the diagnosis.

• Activate EVAP diagnosis.


See also the description of readings in ”Fault diagnosis, general” for more information.

Note

To generate diagnostic troubles the engine temperature must be between 5°C - 40°C. The test is also carried out when the engine is started warm but in that case, it cannot generate diagnostic trouble codes, only report OK. Diagnostic trouble codes can therefore not be generated if the engine is started warm. When carrying out the final check on the rectified fault the diagnostic tool must be used so that Test 1 is initiated irrespective of starting temperature.