Fuel Pump Pressure Test
NOTE:
Begin basic fuel system diagnosis with testing fuel pressure.
- Turn ignition off. Ensure A/C is off (if equipped). Release fuel system pressure. See FUEL SYSTEM PRESSURE RELEASE . Attach Fuel Pressure Gauge Set (J-34730-1 ) to fuel rail or fuel supply line. See Fig 1 . Turn ignition on. Allow fuel pump to run for about 2 seconds. Check fuel pressure. See FUEL PUMP PERFORMANCE .
- With engine at normal operating temperature, turn ignition on and let fuel pressure build to maximum pressure. Start engine and observe pressure. See FUEL PUMP PERFORMANCE . If pressure drop is as specified, system is operating properly. If pressure does not drop as specified, see appropriate FUEL SYSTEM DIAGNOSIS procedure. Locate and repair leak or restriction in fuel system.
FUEL PUMP PERFORMANCE
| Application | Specification | |
|---|---|---|
| Amigo, Rodeo, Passport, Trooper & SLX | ||
| Operating Pressure | 42-55 psi (3.0-3.9 kg/cm2 ) | |
| Pressure Drop | 3-15 psi (0.2-1.1 kg/cm2 ) | |
| Hombre | ||
| Operating Pressure | 41-47 psi (2.9-3.3 kg/cm2 ) | |
| Pressure Drop | 3-10 psi (0.2-0.7 kg/cm2 ) | |