Contents: Pressure release ⇊ Inspection ⇊
Pressure release
Before disconnecting the fuel hoses and pipes, relieve pressure from the system by loosening the service bolt on the top of the fuel filter.
Do not smoke while working on the fuel system. Keep open flames and sparks away from your work area.
When relieving fuel pressure, make sure the ignition switch is off.
1. Disconnect the negative battery cable from the negative battery terminal.
2. Remove the fuel tank cap.
3. Place a socket wrench on the service bolt on the fuel filter while holding the special bolt with another wrench.
4. Cover the service bolt with a rag or paper towel.
5. Slowly loosen the service bolt one full turn.
Note:
- A fuel pressure gauge can be attached to the service bolt hole.
- Always replace the seal between the service bolt and the special bolt whenever you loosen the service bolt.
- When removing bolts, always replace all seals with new ones.
Inspection
1. Relieve fuel pressure.
2. Remove the service bolt on the fuel filter while holding the special bolt with another wrench. Attach the special wrench.
3. Start the engine. Measure the fuel pressure with the engine idling and the fuel pressure regulator vacuum hose disconnected from the fuel pressure regulator and pinched.
The pressure should be:
- engine D15Z6, D1527: 226-275 kPa (2.3-2.8 kgf/cm²)
- engine D16U7, D16Y6, D16Y8: 265-314 kPa (2.7-3.2 kgf/cm²)
- engine A16A2, B16A4, B16A5, B16A6: 275-324 kPa (2.8-3.3 kgf/cm²)
4. Connect the vacuum hose to the fuel pressure regulator.
The pressure should be:
- engine D15Z6, D15Z7: 162-211 kPa (1.65-2.15 kgf/cm²)
- engines D16Y7, D16Y6, D16Y5, D16Y8: 196-245 kPa (2.6-2.5 kgf/cm²)
- engines A16A2, B16A4, B16A5, B16A6: 196-245 kPa (2.0-2.5 kgf/cm²)
If the engine does not start, turn the ignition switch ON(fl), wait 2 seconds, turn it off, then turn it on again and check the fuel pressure readings,
If the fuel pressure is not within specification, first check the fuel pump. IF the fuel pump is OK, check the following:
If fuel pressure is higher than specification, inspect:
- The fuel return line and hose are pinched or clogged,
- The fuel pressure regulator is faulty.
If fuel pressure is below specification, inspect:
- The fuel filter is clogged.
- The fuel pressure regulator is faulty.
- Leak in the fuel line.