| PART NUMBER | TOOL NAME |
| HD-48650 | DIGITAL TECHNICIAN II |
Warning! Stop the engine when refueling or servicing the fuel system. Do not smoke or allow open flame or sparks near gasoline. Gasoline is extremely flammable and highly explosive, which could result in death or serious injury.
The fuel pump delivers fuel to the fuel hose, a cavity in the induction module that supplies the fuel injectors, and to the pressure regulator. Excess fuel pressure is bypassed to the fuel tank through the pressure regulator.
The fuel pump can be turned on with DIGITAL TECHNICIAN II (Part # HD-48650).
Improper fuel system pressure may contribute to one of the following conditions:
- Cranks, but does not run.
- Cuts out (may feel like ignition problem).
- Hesitation, loss of power or poor fuel economy.
Testing
| PART NUMBER | TOOL NAME |
| HD-41142 | FUEL PRESSURE GAUGE |
| HD-44061 | FUEL PRESSURE GAUGE ADAPTER |
Connect the fuel pressure gauge
1. Purge the fuel supply hose and disconnect the fuel supply hose from the fuel pump module.
- a. XL Models: See 4.4 FUEL TANK: XL MODELS.
- b. XR 1200X:See 4.5 FUEL TANK: XR 1200X.
2. Connect the fuel pump connector [141].
Note. Do not kink the fuel hose when installing or removing fuel pressure gauge and adapter.
3. See Figure 4-81. Attach the FUEL PRESSURE GAUGE ADAPTER (Part # HD-44061) as follows:
- a. See Figure 4-82. Pull up on sleeve of fuel tank quickconnect fitting (2) and insert neck of the fuel pressure gauge adapter (3) into quick-connect fitting.
- b. Push up on bottom of adapter and pull down on sleeve until it clicks. Tug on adapter to verify that it is locked in place.
- c. In the same manner, connect vehicle's fuel supply hose fitting (1) to quick-connect fitting (4) on the adapter.
Figure 4-81. Fuel pressure gauge adapter (part # HD-44061): 1. Quick-connect fitting; 2. Protective cap; 3. Fuel tank fitting (neck)
Figure 4-82. Assembling adapter, gauge and fuel supply hose to fuel tank: all models: 1. Fuel supply hose fitting; 2. Fuel tank quick-connect fitting; 3. Fuel pressure gauge adapter; 4. Adapter quick-connect fitting; 5. Pressure adapter/Schroeder valve fitting; 6. Fuel valve (closed position)
Warning! To prevent spray of fuel, be sure quick-connect fittings are properly mated. Gasoline is extremely flammable and highly explosive, which could result in death or serious injury.
4. Verify that the fuel valve (6) and air bleed petcock on the fuel pressure gauge are closed.
5. See Figure 4-83. Remove protective cap from free end of fuel pressure gauge adapter.
Figure 4-83. Fuel pressure gauge installed: all models
6. Connect the FUEL PRESSURE GAUGE (Part # HD-41142) to the Schroeder valve.
Perform test
1. Start and idle engine to pressurize the fuel system. Open the fuel valve to allow the flow of fuel down the hose of the pressure gauge.
2. Purge air from gauge and hose:
- a. Position the clear air bleed tube in a suitable container.
- b. Open and close the air bleed petcock to purge the gauge and hose of air.
- c. Repeat this step several times until only solid fuel (without bubbles) flows from the air bleed tube.
- d. Close the petcock.
3. Open and close throttle to change engine speed. Note the reading of the pressure gauge.
4. Turn the engine OFF and service as necessary. Refer to Table 4-3.
Table 4-3. Fuel pressure test
| RESULTS | CAUSE | SOLUTION |
| Less than: 55 psi (380 kPa) | Restricted fuel filter | Replace. |
| Restricted pump inlet screen | Clean. | |
| Restricted fuel line or hose to gauge | Clear. | |
| Faulty fuel pump | Replace. | |
| Restricted check valve fitting | Clear. | |
| Leak inside tank (hose or coupling) | Repair or replace as necessary. | |
| Faulty pressure regulator | Replace. | |
| Steady at: 55-62 psi (380-425 kPa) | Operating fuel pressure | |
| More than: 62 psi (425 kPa) | Check valve fitting and fuel tank | Replace as necessary. |
| Fuel pressure regulator | Replace. | |
Return to service
1. Position the air bleed tube in a suitable container. Open the air bleed petcock to relieve the fuel system pressure and purge the pressure gauge of gasoline.
Warning! Gasoline can drain from the adapter when gauge is removed. Gasoline is extremely flammable and highly explosive, which could result in death or serious injury. Wipe up spilled fuel immediately and dispose of rags in a suitable manner.
2. Remove fuel pressure gauge from the adapter. Install protective cap over Schroeder valve.
Warning! Gasoline can drain from the fuel line and adapter when removed. Gasoline is extremely flammable and highly explosive, which could result in death or serious injury. Wipe up spilled fuel immediately and dispose of rags in a suitable manner.
3. Pull up on knurled sleeve of the fuel pressure gauge adapter quick-connect fitting and remove vehicle's fuel supply hose from adapter. Release adapter from fuel tank.
Warning! To prevent spray of fuel, be sure quick-connect fittings are properly mated. Gasoline is extremely flammable and highly explosive, which could result in death or serious injury.
4. Push up on release sleeve of fuel pump quick-connect fitting and push the fuel hose fitting into quick-connect fitting. Pull down on release sleeve to lock. Tug on fuel hose fitting to verify that it is locked.