Nissan Altima 2007-2012 Service Manual: Positive crankcase ventilation
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 ventilating air.
The ventilating air is 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 hose connection to the air inlet tubes under all conditions.
Component Inspection
1.CHECK PCV 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.
Is the inspection result normal? YES >> INSPECTION END
NO >> Replace PCV valve.
On board refueling vapor recovery
(ORVR)
Description
From the beginning of refueling, the air and vapor inside the fuel tank go
through refueling EVAP vapor cut
valve and EVAP/ORVR line to the EVAP canister. The vapor is absorbed by t ...
Refrigerant pressure sensor
Description
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 pressur ...
Other materials:
Precaution
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TENSIONER"
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”,
used along
with a front seat belt, helps to reduce the risk or severity of injury to the
dr ...
U124C CD changer
Description
Refer to AV-240, "System Description".
DTC Logic
DTC DETECTION LOGIC
Diagnosis Procedure
1.CHECK CD CHANGER POWER SUPPLY AND GROUND CIRCUIT
Check CD changer power supply and ground circuit. Refer to AV-318, "CD
CHANGER : Diagnosis Procedure".
Do power ...
P0335 CKP sensor (POS)
Description
The crankshaft position sensor (POS) is located on the oil pan facing
the gear teeth (cogs) of the signal plate. It detects the fluctuation of
the engine revolution.
The sensor consists of a permanent magnet and Hall IC.
When the engine is running, the high and low parts of the ...