How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask eric Your Own Question
eric, Automotive Repair Shop Manager
Category: Nissan
Satisfied Customers: 29702
Experience:  Automotive Repair Shop Manager, Technician/JA Mentor
Type Your Nissan Question Here...
eric is online now
A new question is answered every 9 seconds

2004 nissan xterra: i get to the knock sensor to replace it

This answer was rated:

i have a 2004 nissan xterra. how do i get to the knock sensor to replace it and where is it located?



The knock sensor is located underneath the intake manifold on the the engine block. You will have to remove the intake manifold in order to replace it:




  • Drain the cooling system.
  • Relieve the fuel system pressure.
    • Remove or disconnect the following:

    • Negative battery cable
    • Air intake duct
    • Accelerator cable
    • Cruise control cable
    • Idle Air Control (IAC) valve connector
    • Throttle Position (TP) sensor and switch connectors
    • Ignition coil and power transistor connectors
    • Exhaust Gas Recirculation (EGR) Solenoid valve connector
    • EGR temperature sensor connector
    • Radiator hoses
    • Heater hoses
    • Positive Crankcase Ventilation (PCV) valve and hose
    • Evaporative Emissions (EVAP) canister vacuum and purge hoses
    • Brake booster vacuum hose
    • Fuel pressure regulator vacuum hose
    • EGR tube
    • Spark plug wires
    • Distributor
    • Left bank injector connectors
    • Thermal transmitter
    • Upper intake manifold ground cable (VG33)
    • Supercharger (VG33ER)
    • Breather pipe
    • Upper intake manifold (VG33)
    • Intake manifold collector (VG33ER)
    • Fuel lines
    • Right bank injector connectors
    • Fuel supply manifold
    • Engine Coolant Temperature (ECT) sensor connector
    • Lower intake manifold.
    • Loosen the fasteners in the sequence shown.

      Click image to see an enlarged view

    Fig. Intake manifold loosening sequence-3.3L engine


    To install:

    Click image to see an enlarged view

    Fig. Intake manifold torque sequence-3.3L engine

    1. Install the lower intake manifold with a new gasket.
    2. Tighten the fasteners in sequence as follows:
      1. Step 1: 35 inch lbs. (4 Nm)
      2. Step 2: 78 inch lbs. (9 Nm)
      3. Step 3: 70-84 inch lbs. (8-10 Nm)

    3. Install or connect the following:

    4. ECT sensor connector
    5. Fuel supply manifold
    6. Right bank injector connectors
    7. Fuel lines
    8. Upper intake manifold
    9. Breather pipe
    10. Upper intake manifold ground cable
    11. Thermal transmitter
    12. Left bank injector connectors
    13. Distributor
    14. Spark plug wires
    15. EGR tube
    16. Fuel pressure regulator vacuum hose
    17. Brake booster vacuum hose
    18. EVAP canister vacuum and purge hoses
    19. PCV valve and hose
    20. Heater hoses
    21. Radiator hoses
    22. EGR temperature sensor connector
    23. EGR Solenoid valve connector
    24. Ignition coil and power transistor connectors
    25. TP sensor and switch connectors
    26. IAC valve connector
    27. Cruise control cable
    28. Accelerator cable
    29. Air intake duct
    30. Negative battery cable
    31. Fill the cooling system.
    32. Start the engine and check for leaks


    eric and other Nissan Specialists are ready to help you
    Customer: replied 6 years ago.
    do you know how it my cause to get this done a shop?



    You will be looking right at 2.5 hours labor. Labor rates are set by each shop according to its needs, but on average you will be looking at around $80 per hour. So labor will be around $250. knock sensor is around $150 and intake manifold gasket will be around $60. So total at a shop will be around $460 parts and labor