Fuel Pressure: Testing and Inspection
Fuel Pressure Check: QR25DE
Fuel Pressure Release
With SDT
1) Turn ignition switch ON.
2) Perform "FUEL PRESSURE RELEASE" in "Utility" mode with SDT.
3) Start engine.
4) After engine stalls, crank it two or three times to release all fuel pressure.
5) Turn ignition switch OFF.
Without SDT
6) Remove fuel pump fuse located in IPDM E/R.
7) Start engine.
8) After engine stalls, crank it two or three times to release all fuel pressure.
9) Turn ignition switch OFF.
10) Reinstall fuel pump fuse after servicing fuel system.
Fuel Pressure Check
CAUTION:
Before disconnecting fuel line, release fuel pressure from fuel line to eliminate danger.
NOTE:
Prepare pans or saucers under the disconnected fuel line because the fuel may spill out. The fuel pressure cannot be completely released because S01 models do not have fuel return system.
Method A
CAUTION:
- The fuel hose connection method used when taking fuel pressure check must not be used for other purposes.
- Be careful not to scratch or put debris around connection area when servicing, so that the quick connector maintains seal ability with O-rings inside.
- Never perform fuel pressure check with electrical systems operating (i.e. lights, A/C, etc.) Fuel pressure gauge may indicate false readings due to varying engine load and changes in manifold vacuum.
1) Release fuel pressure to zero. Refer to "FUEL PRESSURE RELEASE".
2) Prepare fuel hose for fuel pressure check, and connect fuel pressure gauge.
- Use suitable fuel hose for fuel pressure check (genuine fuel hose without quick connector).
- To avoid unnecessary force or tension to hose, use moderately long fuel hose for fuel pressure check.
- Never use the fuel hose for checking fuel pressure with damage or cracks on it.
- Use Pressure Gauge to check fuel pressure.
3) Remove fuel hose. Refer to [Intake Manifold: Removal and Installation] Intake Manifold Removal and Installation.
- Never twist or kink fuel hose because it is plastic hose.
- Never remove fuel hose from quick connector.
- Keep the original fuel hose to be free from intrusion of dust or foreign substances with a suitable cover.
4) Install the fuel pressure gauge as shown in the figure.
- Wipe off oil or dirt from hose insertion part using cloth moistened with gasoline.
- Apply proper amount of gasoline between top of the fuel tube and No.1 spool.
- Insert fuel hose for fuel pressure check until it touches the No.1 spool on fuel tube.
- Use genuine hose clamp (part number: 16439-N4710 or 16439-40U00).
- When reconnecting fuel line, always use new clamps.
- When reconnecting fuel hose, check the original fuel hose for damage and abnormality.
- Use a torque driver to tighten clamps.
- Install hose clamp to the position within 1 - 2 mm (0.04 - 0.08 in).
- Make sure that clamp screw does not contact adjacent parts.
5) After connecting fuel hose for fuel pressure check, pull the hose with a force of approximately 98 N (10 kg, 22 lb) to confirm fuel tube does not come off.
6) Turn ignition switch ON, and check for fuel leakage.
7) Start engine and check for fuel leakage.
8) Read the indication of fuel pressure gauge.
- Never perform fuel pressure check with system operating. Fuel pressure gauge may indicate false readings.
- During fuel pressure check, confirm for fuel leakage from fuel connection every 3 minutes.
9) If result is unsatisfactory, go to next step.
10) Check the following.
- Fuel hoses and fuel tubes for clogging
- Fuel filter for clogging
- Fuel pump
- Fuel pressure regulator for clogging
If OK, replace fuel level sensor unit, fuel filter and fuel pump assembly.
If NG, repair or replace.
Method B
CAUTION:
- Be careful not to scratch or get the fuel hose connection area dirty when servicing, so that the quick connector o-ring maintains seal ability.
- Use Fuel Pressure Gauge Kit [SST (J-44321)] and Fuel Pressure Gauge Adapter [SST (J-44321-6)] to check fuel pressure.
11) Release fuel pressure to zero. Refer to "FUEL PRESSURE RELEASE".
12) Remove fuel hose using Quick Connector Release [SST (J-45488)]. Refer to [Fuel Injector and Fuel Tube: Removal and Installation [QR25DE] Removal and Installation ].
- Never twist or kink fuel hose because it is plastic hose.
- Never remove fuel hose from quick connector.
- Keep fuel hose connections clean.
13) Install Fuel Pressure Gauge Adapter [SST (J-44321-6)] and Fuel Pressure Gauge kit [SST (J-44321)] as shown in the figure.
- Never distort or bend fuel rail tube when installing fuel pressure gauge adapter.
- When reconnecting fuel hose, check the original fuel hose for damage and abnormality.
14) Turn ignition switch ON (reactivate fuel pump), and check for fuel leakage.
15) Start engine and check for fuel leakage.
16) Read the indication of fuel pressure gauge kit [SST (J-44321)].
- During fuel pressure check, check for fuel leakage from fuel connection every 3 minutes.
17) If result is unsatisfactory, go to next step.
18) Check the following.
- Fuel hoses and fuel tubes for clogging
- Fuel filter for clogging
- Fuel pump
- Fuel pressure regulator for clogging
If OK, replace fuel level sensor unit, fuel filter and fuel pump assembly.
If NG, repair or replace.
19) Before disconnecting Fuel Pressure Gauge kit [SST (J-44321)] and Fuel Pressure Adapter [SST (J-44321-6)], release fuel pressure to zero. Refer to "FUEL PRESSURE RELEASE".