Operation CHARM: Car repair manuals for everyone.
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Fuel Pressure: Testing and Inspection

Fuel Line Removal:





- Check that battery voltage is approx. 12 volts. Disconnect the cable from the negative (-) terminal of the battery.




- Put a suitable container or shop towel under the fuel filter.
- Remove the union bolt and two gasket, and disconnect the fuel inlet hose from the fuel filter outlet.

HINT: Slowly loosen the union bolt.

Gauge Installation:





- Install the fuel inlet hose and pressure gauge to the fuel filter outlet with three new gaskets.

Torque: 29 N-m (300 kgf.cm, 22 ft.lbs)

- Wipe off any splattered gasoline.
- Reconnect the battery negative (-) cable.

Jumper Wire Installation:





- Using a jumper wire, connect terminals +B and FP of the data link connector 1.

Fuel Pressure Measurement:





- Turn the ignition switch ON. Measure the fuel pressure.

Fuel pressure:
281 - 287 kPa
(2.87 - 2.93 kgf/cm2, 40.8 - 41.7 psi)

- If pressure is high, replace the fuel pressure regulator. If pressure is low, check the following parts:
^ Fuel hoses and connection
^ Fuel pump
^ Fuel filter
^ Fuel pressure regulator



Fuel Pressure Measurement - No Vacuum To Regulator:





- Start the engine.
- Disconnect the vacuum sensing hose from the fuel pressure regulator and plug the hose end.
- Measure the fuel pressure at idle.

Fuel pressure:
281 - 287 kPa
(2.87 - 2.93 kgf/cm2, 40.8 - 41.7 psi)


Fuel Pressure Measurement - Vacuum To Regulator:





- Reconnect the vacuum sensing hose to the fuel pressure regulator.
- Measure the fuel pressure at idle.

Fuel pressure:
226 - 265 kPa
(2.3 - 2.6 kgf/cm2, 33 - 37 psi)

- If pressure is not as specified, check the vacuum sensing hose and fuel pressure regulator.
- Stop the engine. Check that the fuel pressure remains 147 kPa (1.5 kgf/cm2, 21 psi) or more for 5 minutes after the engine is turned off.
- If pressure is not as specified, check the fuel pump, pressure regulator and/or injector.
- After checking fuel pressure, disconnect the battery negative (-) cable and carefully remove the gauge to prevent gasoline from splashing.
- Connect the fuel inlet hose with two new gaskets and the union bolt.

Torque: 29 N-m (300 kgf.cm, 22 ft.lbs)

- Reconnect the cable to the negative (-) terminal of the battery.
- Check for fuel leakage.