LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Nissan-Datsun >> 2012 >> Quest LE >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Component Testing >> Variable Induction Air System >> Diagnosis Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnosis Procedure

  1. INSPECTION START

    Confirm the malfunctioning system (power valve 1 or power valve 2). Refer to "COMPONENT FUNCTION CHECK ".

    Which system is related to the incident? 

    Power valve 1: GO TO 2.

    Power valve 2: GO TO  6.

  2. CHECK VACUUM EXISTENCE-I

    With CONSULT 

    1. Stop engine and disconnect vacuum hose connected to power valve actuator 1.
    2. Start engine and let it idle.
    3. Perform "VIAS S/V-1" in "ACTIVE TEST" mode with CONSULT.
    4. Turn VIAS control solenoid valve 1 ON and OFF, and check vacuum existence under the following conditions.
      VIAS S/V-1 Vacuum
      ON Existed
      OFF Not existed

    Without CONSULT 

    1. Stop engine and disconnect vacuum hose connected to power valve actuator 1.
    2. Disconnect VIAS control solenoid valve 1 harness connector.
    3. Start engine.
    4. Rev engine quickly up to approximately 5, 000 rpm.
    5. Check vacuum existence under the following conditions.
      Condition Vacuum
      Idle Existed
      Rev engine quickly up to approximately 5, 000 rpm Not existed

      Is the inspection result normal? 

      YES: Repair or replace power valve actuator 1. Refer to "ENGINE CONTROL SYSTEM: COMPONENT PARTS LOCATION ".

      NO: GO TO 3.

  3. CHECK VACUUM TANK
    1. Stop engine and disconnect vacuum hose connected to intake manifold collector.
    2. Start engine and let it idle.
    3. Check vacuum existence from intake manifold collector.

      Does vacuum existence from the intake manifold collector? 

      YES: GO TO 4.

      NO: Replace intake manifold collector. Refer to "EXPLODED VIEW ".

  4. CHECK VACUUM HOSE
    1. Stop engine.
    2. Check vacuum hose for crack, clogging, improper connection or disconnection. Refer to "VARIABLE INDUCTION AIR SYSTEM: SYSTEM DESCRIPTION ".

      Is the inspection result normal? 

      YES: GO TO 5.

      NO: Repair hoses or tubes.

      Fig 1: Checking Vacuum Hoses
      G08171600Courtesy of NISSAN NORTH AMERICA, INC.
  5. CHECK VIAS CONTROL SOLENOID VALVE 1

    Check VIAS control solenoid valve 1. Refer to "COMPONENT INSPECTION ".

    Is the inspection result normal? 

    YES: GO TO  8.

    NO: Replace VIAS control solenoid valve 1. Refer to "EXPLODED VIEW ".

  6. CHECK VACUUM EXISTENCE-II

    With CONSULT 

    1. Stop engine and disconnect vacuum hose connected to power valve actuator 2.
    2. Start engine and let it idle.
    3. Perform "VIAS S/V-2" in "ACTIVE TEST" mode with CONSULT.
    4. Turn VIAS control solenoid valve 2 ON and OFF, and check vacuum existence under the following conditions.
      VIAS S/V 2 Vacuum
      ON Existed
      OFF Not existed

    Without CONSULT 

    1. Stop engine and disconnect vacuum hose connected to power valve actuator 2.
    2. Disconnect VIAS control solenoid valve 1 harness connector.
    3. Start engine.
    4. Rev engine quickly up to approximately 5, 000 rpm.
    5. Check vacuum existence under the following conditions.
      Condition Operation
      Idle Existed
      Rev engine quickly up to approximately 5, 000 rpm Not existed

      Is the inspection result normal? 

      YES: Repair or replace power valve actuator 2. Refer to "ENGINE CONTROL SYSTEM: COMPONENT PARTS LOCATION ".

      NO: GO TO 7.

  7. CHECK VACUUM HOSE
    1. Stop engine.
    2. Check vacuum hose for crack, clogging, improper connection or disconnection. Refer to "VARIABLE INDUCTION AIR SYSTEM: SYSTEM DESCRIPTION ".

      Is the inspection result normal? 

      YES: GO TO 8.

      NO: Repair hoses or tubes.

      Fig 2: Checking Vacuum Hoses
      G08171601Courtesy of NISSAN NORTH AMERICA, INC.
  8. CHECK VIAS CONTROL SOLENOID VALVE 2

    Check VIAS control solenoid valve 2. Refer to "COMPONENT INSPECTION ".

    Is the inspection result normal? 

    YES: Check intermittent incident. Refer to "INTERMITTENT INCIDENT ".

    NO: Replace VIAS control solenoid valve 2. Refer to  "EXPLODED VIEW ".