Fuel Pressure Test

Start engine. Warm to normal operating temperature. Turn ignition off. Release fuel system pressure. See FUEL SYSTEM PRESSURE RELEASE . Remove plug bolt on fuel rail. Install coupling, pressure gauge and hose to fuel rail. See Fig 1 . Verify battery voltage is 11 volts or greater. Start engine and ensure no leakage exists at pressure gauge connection. Turn engine off.
Turn ignition on to operate fuel pump for 3 seconds. Turn ignition off. Repeat 3-4 times and check fuel pressure. See FUEL PUMP PERFORMANCE and REGULATED FUEL PRESSURE tables. Start engine. Measure fuel pressure at idle. Turn ignition off.
If pressures are not within specification, check for defective fuel pump, pressure regulator or restriction in fuel system. See CIRCUIT TESTS . Repair as necessary. Remove fuel pressure gauge and start engine to ensure no fuel leakage exists.

Fig 1: Testing Fuel System Pressure (Typical)

Courtesy of SUZUKI OF AMERICA CORP.

FUEL PUMP PERFORMANCE

Application

⁽¹⁾ psi (kg/cm² )

1.8L

⁽²⁾ 38.4-44.0 (2.7-3.1)

⁽¹⁾	Key on and engine off.

⁽²⁾	Pressure should maintain at least 28.4 psi (2.0 kg/cm² ) for one minute after fuel pump is turned off.

REGULATED FUEL PRESSURE

Application

⁽¹⁾ psi (kg/cm² )

1.8L

⁽²⁾ 31.0-37.0 (2.2-2.6)

⁽¹⁾	With engine idling.

⁽²⁾	Pressure should maintain at least 28.4 psi (2.0 kg/cm² ) for one minute after fuel pump is turned off.