How to Repair a Fuel Sending Unit on a CRX

The fuel sending unit is part of the fuel pump assembly on a Honda CRX. The 1988 through 1991 model years were the only models equipped with electronic fuel injection, thus requiring a sending unit. The actual unit is located inside the gas tank and is only accessible by removing the tank. Because you will often not be able to separate the fuel pump from the fuel sending unit (there is a high probability that the fuel pump will be damaged during the process), troubleshoot the problem first before replacing the sending unit. In almost every case, you'll need to replace both the sending unit and the fuel pump.

Things You'll Need

• Socket wrench with socket set
• Open-end wrench set
• Low profile jack with jack stands
• Gas container/catch pan
• Siphon
• Wheel blocks
• Permanent marker
• Masking tape

Instructions

Check the Fuel Pump

1. Put the key into the ignition and turn it to the "II" position. You should hear a hum for one to two seconds. This is the fuel pump relay being energized.

2. Try to start the CRX even if you don't hear the fuel pump relay energize. If the vehicle will not turn over, this could indicate that the relay may be malfunctioning.

3. Open the gas tank door and slowly turn the fuel filler cap counterclockwise. Hold pressure on the filler cap and listen for the system to depressurize as you remove the cap. If you don't hear what will sound like air escaping, the fuel system is not pressurizing. This can indicate that the fuel pump and sending unit have failed.

4. Try to pop start the vehicle if you have a five-speed CRX. Have an assistant (or several assistants) push the CRX from the rear while you hold in the clutch and put the car in first gear. When the car has gained momentum, rapidly release the clutch and press on the accelerator. Your CRX's engine should start and you should be able to drive normally. If pop starting the vehicle does not work, replace the vehicle's fuel pump and sending unit.

Replace the Fuel Sending Unit

1. Remove the drain bolt on the rear of the CRX's gas tank with a socket wrench. If your CRX does not contain the drain plug, then insert one end of a siphon into the gas tank and squeeze the pump on the siphon until gasoline is drawn up the siphon tube. Drain the gas tank into a catch pan approved for holding gasoline.

2. Place wheel blocks in front of the front wheels and lift up the rear of the CRX with a floor jack. You must lift up on the rear jack point, which is an extension of the frame. Some models of CRX have a center rear tow hook that you must lift up on.

3. Place a jack stand under each of the tow hooks located on the right and left side of the CRX and lower the car onto the stands.

4. Label all of the fuel lines and where they are connected with a marker and masking tape.

5. Disconnect all of the fuel lines using an open-end wrench.

6. Support the fuel tank with the floor jack.

7. Disconnect both of the fuel tank retaining straps and pivot them downwards until they are out of the way.

8. Lower the fuel tank until you are able to disconnect all of the electrical connections for the ground strap, fuel pump and fuel pump sending unit.

9. Remove the tank from the CRX.

10. Remove the mounting nuts for the fuel pump, and pull the pump and sending unit out of the fuel tank.

11. Remove the sock filter from the end of the fuel pump.

12. Install the new fuel pump and sending unit. Installation is the reverse of removal.

References

• "Honda Civic, CRX and Wagon Repair & Service Manual 1984-1991"; Mike Stubblefield, Robert Maddox, John H. Haynes; 1992