Signs of a Failing Fuel Pump in a 2022 Toyota Highlander

A failing fuel pump can lead to performance issues and ultimately cause the vehicle to stop running. Below are the common symptoms, diagnostic steps, and repair instructions for a failing fuel pump in a 2022 Toyota Highlander.

Tools Required

• OBD-II Scanner
• Fuel Pressure Gauge
• Multimeter
• Safety Gloves
• Safety Glasses
• Screwdrivers (Flat and Phillips)
• Ratchet Set
• Pliers
• Fuel Line Disconnect Tool

Step-by-Step Diagnostic Process

1. Check for Diagnostic Trouble Codes (DTCs)

   • Use an OBD-II scanner to check for any stored trouble codes related to fuel delivery (e.g., P0087, P0191). Record any codes for further analysis.

2. Visual Inspection

   • Inspect the fuel pump fuse in the fuse box. Replace if blown.
   • Check the wiring and connectors to the fuel pump for signs of damage, corrosion, or loose connections.

3. Fuel Pressure Test

   • Connect a fuel pressure gauge to the fuel rail. The expected pressure for a 2022 Highlander is typically around 50-60 psi.
   • Turn the ignition to the “ON” position without starting the engine. Check the fuel pressure reading.
   • If the pressure is below specification, the fuel pump may be failing.

4. Electrical Testing

   • Use a multimeter to check the voltage at the fuel pump connector while the ignition is turned to the ON position.
   • If there is no voltage or if it’s below the expected 12V, there may be an issue with the fuel pump relay or wiring.

5. Listen for Pump Operation

   • With the key in the ON position, listen for a humming sound from the fuel tank for about 2 seconds. If there’s no sound, the pump may not be functioning.

Repair Instructions

Tools Required

• Replacement Fuel Pump
• Ratchet and Socket Set
• Screwdrivers
• Pliers
• Fuel Line Disconnect Tool
• Safety Glasses
• Safety Gloves
• Towels (for fuel spills)

Step-by-Step Repair Process

1. Safety First

   • Ensure the vehicle is parked on a level surface and the ignition is off. Disconnect the negative battery terminal.

2. Relieve Fuel Pressure

   • Remove the fuel pump relay from the fuse box and start the engine until it stalls to relieve fuel pressure. Turn off the ignition.

3. Access the Fuel Pump

   • Depending on the vehicle configuration, you may need to remove the rear seats or access the fuel pump through the trunk. Locate the fuel pump access panel and remove it.
   • If no access panel is available, you will need to drain the fuel tank and remove it.

4. Disconnect Fuel Lines and Electrical Connectors

   • Use a fuel line disconnect tool to detach the fuel lines from the pump.
   • Disconnect the electrical connector from the fuel pump.

5. Remove the Old Fuel Pump

   • Unscrew and remove the retaining ring or screws that hold the fuel pump assembly in place. Carefully lift the assembly out of the tank.

6. Install the New Fuel Pump

   • Install the new fuel pump into the assembly. Make sure to replace any O-rings or seals.
   • Reinstall the fuel pump assembly into the tank and secure it with the retaining ring or screws.

7. Reconnect Fuel Lines and Electrical Connectors

   • Reattach the fuel lines to the pump and reconnect the electrical connectors.

8. Reassemble the Vehicle

   • If you removed the rear seats or access panel, reassemble them.

9. Reconnect Battery and Test

   • Reconnect the negative battery terminal. Install the fuel pump relay back into the fuse box.
   • Turn the ignition to the ON position and check for leaks around the fuel lines.

10. Start the Engine

• Start the engine and let it run for a few minutes. Monitor for any abnormal noises, leaks, or performance issues.

Conclusion

If the symptoms persist after replacing the fuel pump, further diagnostics may be required to check for issues with the fuel filter, fuel injectors, or the engine control unit (ECU). Regular maintenance checks can help prevent future fuel pump failures.