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JamesH, Auto Service Tech
Category: Nissan
Satisfied Customers: 663
Experience:  Auto Service Tech Hands on Nissian Experience
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Where is the gas filter locted on a 2003 Nissan Altima My

Resolved Question:

Where is the gas filter locted on a 2003 Nissan Altima?

My car keepd stalling out on me and so far I have changed the crank position sensor and the speed sensor which came back from a diagnostic check that I had done. The speed sensor has been changed but when I had it checked again it said that something was still wrong with the speed sensor and I came to find out that there was a shortage in the harness. Could this be the cause of my car to keep cutting off or could there be something else wrong with it. when the car cuts off (whenever it so please its hard to get it to start back up its like a hard start what is the cause? Speed sensor wire or harness shortage or could it be the gas filter or something else and I also had a tune up done on the car.
Submitted: 7 years ago.
Category: Nissan
Expert:  JamesH replied 7 years ago.
Yes a short in the speed sensor could cause this but also the fuel system can be the cause. I have attached the steps to do a fuel pressure test on the system if its not within specs you start by replacing the fuel filter. I have also attached where the fuel filter is. Let me know if you have any questions. Thanks! Below if for the 3.5 motor



  • Use Fuel Pressure Gauge Kit (J-44321) to check fuel pressure.
  1. Release fuel pressure to zero. Refer to "FUEL PRESSURE RELEASE".

  1. Install the inline fuel quick disconnect fitting between the connection of the fuel feed hose (from tank) and the fuel hose (to engine).
  2. Connect the fuel pressure test gauge (quick connect adapter hose) to the quick disconnect fitting.
  3. Turn ignition switch ON and check for fuel leakage.
  4. Start engine and check for fuel leakage.
  5. Read the indication of fuel pressure gauge. At idling: Approximately 350 kPa (3.7 kg/, 51 psi)
  6. If result is unsatisfactory, go to next step.
  7. Check the following.
    • Fuel hoses and fuel tubes for clogging
    • Fuel filter for clogging
    • Fuel pump
    • Fuel pressure regulator for clogging If OK, replace fuel pressure regulator.

If NG, repair or replace.


Removal And Installation


WARNING: Read "General Precautions" before working on the fuel system. Refer to "General Precautions".

  1. Unscrew the fuel filler cap to release the pressure inside the fuel tank.
  2. Release the fuel pressure from the fuel lines. Refer to "FUEL PRESSURE RELEASE" (QR25DE), "FUEL PRESSURE RELEASE" (VQ35DE).
  3. Remove the rear seat bottom.

  1. Remove the fuel pump inspection hole cover.
  2. Disconnect the harness connector, and fuel feed hose from the fuel level sensor unit, fuel filter, and fuel pump assembly.

Remove the quick connector as follows:

  • Hold the sides of the connector, push in tubs and pull out the tube.
  • If the connector and the tube are stuck together, push and pull several times until they start to move. Then disconnect them by pulling.


  • The tube can be removed when the tabs are completely depressed. Do not twist it more than necessary.
  • Do not use any tools to remove the quick connector.
  • Keep the resin tube away from heat. Be especially careful when welding near the tube.
  • Prevent acid liquid such as battery electrolyte, etc. from getting on the resin tube.
  • Do not bend or twist the tube during installation and removal.
  • Only when the tube is replaced, remove the remaining retainer on the tube or fuel level sensor, fuel filter, and fuel pump assembly.
  • When the tube or fuel level sensor, fuel filter, and fuel pump assembly is replaced, also replace the retainer with a new one (green colored retainer).

  • To keep the connecting portion clean and to avoid damage and foreign materials, cover them completely with plastic bags or something similar.

  1. Using a lock ring wrench, remove the lock ring.

  1. Remove the fuel level sensor, fuel filter, and fuel pump assembly. CAUTION: Do not bend the float arm during removal.

Make sure the fuel level sensor, fuel filter, and fuel pump is free from defects and foreign materials.

Installation is in the reverse order of removal.

  • Install the fuel level sensor, fuel filter, and fuel pump assembly with the front mark (arrow) facing the front of the vehicle.

  • Connect the quick connector as follows:
  1. Check the connection for damage or any foreign materials.
  2. Align the connector with the tube, then insert the connector straight into the tube until a click is heard.
  3. After the tube is connected, make sure the connection is secure by performing the following checks:
    • Pull the tube and the connector to make sure they are securely connected.

  • Visually confirm that the two retainer tabs are connected to the quick connector.


  • Use the following procedure to check for fuel leaks.
  1. Turn the ignition switch to ON (without starting the engine). Then check the connections for fuel leaks by applying fuel pressure to the fuel piping.
  2. Start the engine and let it idle and make sure there are no fuel leaks at the fuel system connections.




Customer: replied 7 years ago.

where is the fuel pump located in a 2003 nissan altima?


Expert:  JamesH replied 7 years ago.
It is located inside the fuel tank. accessible from under the rear seat.
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