Curiosii for ever!: Car repair manuals for everyone.

Fuel Pressure: Testing and Inspection

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

CAUTION: Work must be started after approx. 20 seconds or longer from the time the ignition switch is turned to the "LOCK" position and the negative (-) terminal cable is disconnected from the battery.

Union Bolt:





- Remove the union bolt and two gaskets, and disconnect the fuel inlet hose from the delivery pipe.

HINT:
^ Put a suitable container or shop towel under the cold start injector pipe.
^ Slowly loosen the union bolt.

Gauge Installation:





- Install the fuel inlet hose and pressure gauge to the delivery pipe with three new gaskets and union bolt.

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

- Wipe off any splattered gasoline.

Jumper Installation:





- Using a jumper wire, connect terminals +B and FP of the check connector.
- Reconnect the battery negative (-) cable.

Reading Fuel Pressure:





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

Fuel pressure:
226 - 265 kPa (2.3 - 2.7 kgf/cm2, 33 - 38 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
- Remove jumper wire.
- Start the engine.

Reading Fuel Pressure - No Vacuum To Regulator:





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

Fuel pressure:
226 - 265 kPa (2.3 - 2.7 kgf/cm2, 33 - 38 psi)

Reading Fuel Pressure - Vacuum To Regulator:





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

Fuel pressure:
186 - 216 kPa (1.9 - 2.2 kgf/cm2, 27 - 31 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.