REMOVAL & INSTALLATION
The radio may contain a coded theft protection circuit. Always obtain the code number before disconnecting the battery.
- Disconnect the negative battery cable.
- Loosen the fuel filler cap. Then, loosen the fuel filter service bolt to relieve the fuel pressure.
- Remove the rear seat cushions (Civic), or the rear compartment trim (Civic del Sol).
- Remove the fuel pump access panel.
- Disconnect the two-wire fuel pump harness.
- Clean the fuel line fittings before disconnecting them.
- Disconnect the fuel line and the hose from the fuel pump.
- Unbolt the fuel pump and lift it out the fuel tank. Allow the fuel in the pump drain into the tank before removing the pump from the vehicle.
- Disconnect and remove the fuel pump motor from its bracket.
Use new sealing washers when reconnecting the fuel line banjo bolt.
- Install the fuel pump into the fuel tank with a new O-ring. Then, tighten the mounting nuts to 4 ft. lbs. (6 Nm).
- Reconnect the hose and the fuel line. Carefully tighten the banjo bolt to 20 ft. lbs. (28 Nm). Reconnect the fuel pump harness.
- Tighten the fuel filler cap. Tighten the fuel filter service bolt to 11 ft. lbs. (15 Nm).
- Connect the battery cable and turn the ignition switch ON and OFF several times to pressurize the fuel system.
- Check the connections at the fuel pump for any leaks. Check the fuel filter service bolt for leaks.
- Install the fuel pump access cover.
- Install the rear seat cushions or rear compartment trim. Be sure the clips are properly seated.
TESTING THE FUEL PUMP CIRCUIT
If you suspect a problem with the fuel pump, listen for the pump to operate by removing the fuel fill cap and checking to see if the pump can be heard running during the first two seconds after the ignition key is turned to the "ON" position. You should hear the fuel pump motor run.
If the fuel pump can be heard running, the fuel pump's electrical circuit is likely to be ok and the fuel pump operating pressure should be checked.
Once the engine has started, the fuel pump operation is controlled by the Engine Control Module/Powertrain Control Module (ECM/PCM) via the PGM-FI Main Relay. The fuel pump receives its electrical power from the PGM-FI Main Relay, which is triggered for two seconds when the ignition switch is initially turned to the on position.
After the initial two-second startup signal is received, the PGM-FI Main Relay is controlled by the ECM/PCM. Because the fuel pump receives its power from the PGM-FI Main Relay, a problem with the ignition switch, ECM/PCM, or electrical wiring may not allow battery voltage to reach the pump.
To check the fuel pump wiring proceed as follows:
- Make sure the ignition switch is in the off position.
- Locate and disconnect the fuel pump electrical connector at the fuel tank.
- You may have to remove the floor access panel. For specific details, see the fuel pump removal procedure.
Fuel pump access is limited on early 1996 models of the Civic and Civic del Sol, and may require you to work under the vehicle. Perform the following steps, if that is the situation:
- Raise the vehicle and safely support it on suitable jackstands.
- Remove the protective cover for the fuel tank fuel hoses.
- Detach the fuel pump electrical connector.
- Connect a suitable Voltmeter between the fuel pump positive terminal of the electrical connector and a known good chassis ground.
- Hold the electrical connector of the PGM-FI Main Relay so the wire side of the female terminals is visible and install a jumper wire between terminal No. 4 and 5.
- When the ignition switch is turned to the on battery voltage should be present at the fuel pump electrical connector.
- If the battery voltage is present, check the fuel pump's ground.
- If the ground is "OK", check the fuel pump.
- If battery voltage is not present, trace the wiring harness and check the cause for an open or shorted circuit.
- If all wiring checks out, test the fuel pressure.
FUEL PUMP PRESSURE TEST
The fuel pressure should be checked at the fuel rail or at the fuel feed line for the fuel rail. The fuel pressure is checked with the engine started, thus the fuel pressure gauge must not interrupt the flow of fuel to the fuel rail and the fuel injectors.
To attach a fuel pressure gauge to the pressurized fuel loop requires the use of an adapter that is capable of safely withstanding the fuel system fuel pressure.
To check the fuel system pressure proceed as follows:
- Remove the fuel filler cap and relieve the residual fuel pressure.
Attach a suitable fuel pressure gauge to the fuel injection fuel loop as follows:
Remove the banjo bolt from the fuel filter outlet and install the pressure gauge using a suitable fitting to temporarily substitute for the banjo bolt and supply fuel to the gauge and the fuel rail.
- Remove and plug the vacuum line for the fuel pressure regulator located near the end of the fuel rail.
Start the engine and note the fuel pressure. With the pressure regulator vacuum hose disconnected and plugged, the fuel pressure should register as follows:
38-46 psi (260-310 kPa)
If the engine wont start, turn on the ignition switch ON, wait two seconds, then turn off the ignition switch OFF. Turn the ignition switch back ON again and read the fuel pressure.
- If the fuel pressure is higher than specification check for a pinched or restricted fuel return hose or line.
- If the fuel pressure is lower than the specification check for a damaged fuel pressure regulator, clogged fuel filter, fuel feed line or a leak in the fuel feed line. If the fuel pressure regulator, fuel feed lines, and fuel pump are ok, replace the fuel pump and fuel filter.
Once the test is complete, perform the following:
- Carefully remove the fuel pressure gauge and test fittings.
- Install the removed fasteners using new sealing washers.
- Install the fuel filler cap.
- Start the engine and check for any fuel leaks, and repair as necessary.