Component Tests and General Diagnostics
WARNING: Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death. Fuel can also irritate skin and eyes. To prevent this, always complete the "BEFORE REPAIR PROCEDURE".1. Disconnect the negative battery cable.
2. Connect a fuel pressure gauge between the fuel filter (high-pressure) and the main fuel hose. install clamps as shown in the figure.
3. Connect the negative battery cable.
4. Short the DLC terminal F/P to body GND using a jumper wire.
CAUTION: Connecting the wrong DLC terminal may possibly cause a malfunction. Carefully connect the specified terminal only.
5. Turn the ignition key to ON to operate the fuel pump.
6. Check the fuel line pressure.
- If the pressure is higher than specification, inspect the fuel pump maximum pressure.
- If the fuel pump maximum pressure is within specification, inspect the fuel return hose or the pressure regulator for clogging.
- If the pressure is lower than specification, go to next step.
Specification:
KL: 270 - 310 kPa {2.7 - 3.2 kgf/sq.cm, 39 - 45 psi}
KJ: 280 - 330 kPa {2.8 - 3.4 kgf/sq.cm, 41 - 48 Psi}
7. Measure the fuel line pressure while clipping the fuel return hose as shown.
- If the fuel line pressure quickly increases, inspect the pressure regulator.
- If the fuel line pressure gradually increases, inspect the fuel pump maximum pressure.
- If the fuel pump maximum pressure is normal, inspect for clogging between fuel pump and pressure regulator.
8. Turn the ignition key to OFF.
9. Disconnect the jumper wire and wait for 5 min.
10. Check the fuel line residual pressure.
- If the pressure is lower than specification, go to next step.
11. Turn the ignition key to ON for approx. 10 s.
12. Check whether the fuel line pressure holds when the ignition switch is turned to OFF after clipping the fuel return hose as shown in the figure.
- If the fuel line pressure holds, replace the pressure regulator.
- If the fuel line pressure does not hold, inspect the fuel pump hold pressure.
- If the fuel pump hold pressure is normal, inspect for fuel leakage from the fuel line and the fuel injector.
Specification: More than 150 kPa {1 .5 kg/sq.cm, 21 psi}
13. Remove the fuel pressure gauge.
14. Connect the main fuel hose to the fuel filter (high-pressure).