Nissan Frontier D40. Manual - part 425

ON BOARD REFUELING VAPOR RECOVERY (ORVR)

EC-391

< COMPONENT DIAGNOSIS >

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EC

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d.

Apply vacuum pressure to hose end [

−

13.3 kPa (

−

100 mmHg, 

−

3.94 inHg)] with fuel gauge retainer

remaining open and check that the pressure is applicable.

BBIA0568E

EC-392

< COMPONENT DIAGNOSIS >

[QR25DE]

POSITIVE CRANKCASE VENTILATION

POSITIVE CRANKCASE VENTILATION

Description

INFOID:0000000005273427

SYSTEM DESCRIPTION

This system returns blow-by gas to the intake manifold.
The positive crankcase ventilation (PCV) valve is provided to conduct crankcase blow-by gas to the intake
manifold. During partial throttle operation of the engine, the intake manifold sucks the blow-by gas through the
PCV valve. Normally, the capacity of the valve is sufficient to handle any blow-by and a small amount of venti-
lating air. The ventilating air is then drawn from the air inlet tubes into the crankcase. In this process the air
passes through the hose connecting air inlet tubes to rocker cover. Under full-throttle condition, the manifold
vacuum is insufficient to draw the blow-by flow through the valve. The flow goes through the hose connection
in the reverse direction.
On vehicles with an excessively high blow-by, the valve does not
meet the requirement. This is because some of the flow will go
through the hoseconnection to the air inlet tubes under all condi-
tions.

Component Inspection

INFOID:0000000005273428

PCV (POSITIVE CRANKCASE VENTILATION) VALVE

With engine running at idle, remove PCV valve from rocker cover. A
properly working valve makes a hissing noise as air passes through
it. A strong vacuum should be felt immediately when a finger is
placed over valve inlet.

PBIB0492E

PBIB1588E

PBIB1589E

POSITIVE CRANKCASE VENTILATION

EC-393

< COMPONENT DIAGNOSIS >

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PCV VALVE VENTILATION HOSE

1.

Check hoses and hose connections for leaks.

2.

Disconnect all hoses and clean with compressed air. If any
hosecannot be freed of obstructions, replace.

S-ET277

EC-394

< COMPONENT DIAGNOSIS >

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REFRIGERANT PRESSURE SENSOR

REFRIGERANT PRESSURE SENSOR

Component Description

INFOID:0000000005273429

The refrigerant pressure sensor is installed at the condenser of the
air conditioner system. The sensor uses an electrostatic volume
pressure transducer to convert refrigerant pressure to voltage. The
voltage signal is sent to ECM, and ECM controls cooling fan system.

Diagnosis Procedure

INFOID:0000000005273430

1.

CHECK REFRIGERANT PRESSURE SENSOR OVERALL FUNCTION

1.

Start engine and warm it up to normal operating temperature.

2.

Turn A/C switch and blower fan switch ON.

3.

Check voltage between ECM terminal 70 and ground with CON-
SULT-III or tester.

OK or NG

OK

>> INSPECTION END

NG

>> GO TO 2.

2.

CHECK GROUND CONNECTIONS

1.

Turn A/C switch and blower fan switch OFF.

2.

Stop engine.

3.

Loosen and retighten two ground screws on the body. Refer to 

EC-90, "Ground Inspection"

.

OK or NG

BBIA0627E

PBIB2657E

Voltage: 1.0 - 4.0V

PBIB1188E

BBIA0614E