Relieve fuel system pressure and verify battery voltage is at least 11 volts. Remove ISC solenoid valve and EGR modulator bracket (if equipped). See Figure .
Separate fuel hose from fuel pipe near fuel rail and attach fuel pressure tester. Remove fuel pump relay from main fuse box leaving wire harness connector attached. Using jumper wire, connect Pink terminal to White/Blue terminal. See Fig 1 .
Turn ignition on. With fuel pump operating and engine off, fuel pressure should be 35.5-38.4 psi (2.5-2.7 kg/cm² ). Turn ignition off and allow one minute for pressure to reduce. Minimum fuel pressure should be 25.6 psi (1.8 kg/cm² ).
Install ISC solenoid valve and start engine to ensure that there is no leakage at pressure gauge connection. Measure and record fuel pressure with engine idling. Fuel pressure should be 25.6-29.9 psi (1.8-2.1 kg/cm² ).
If pressure is not within specification, check for defective fuel pump, pressure regulator or restriction in fuel system. Repair as necessary. Remove pressure gauge and start engine to ensure that no fuel leakage exists.

REGULATED FUEL PRESSURE

Application

⁽¹⁾ Engine Off psi (kg/cm² )

psi (kg/cm² ) At Idle

Swift ⁽²⁾

25.6 (1.8)

25.6-29.9 (1.8-2.1)

⁽¹⁾	After running engine, turn ignition to the "OFF" position.

⁽²⁾	With engine off and ignition in the "ON" position, fuel pressure should be 35.5-38.4 psi (2.5-2.7 kg/cm² ).

Fig 1: Fuel System Test Procedures

Courtesy of SUZUKI OF AMERICA CORP.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Fuel Pressure Test