Turn ignition off. Unplug each injector connector. Measure resistance across both terminals. If resistance is not 13.8 ohms at 68°F (20°C), replace fuel injector.
To check injector spray pattern and volume, relieve fuel system pressure. Remove injectors from engine. Disconnect fuel hose from fuel filter outlet. Use Fuel Pressure Gauge (09268-41045) to "T" fuel injector between fuel filter and fuel pressure regulator. See Fig 1 and Fig 2.
Place injector into clean container. Place tube on end of injector to prevent fuel from spilling. Connect Fuel Injector Tester (09842-30070) or trigger box with appropriate resistor to fuel injector. Turn ignition on, with engine off.
Connect jumper wire to engine check connector terminals FP and +B to pressurize fuel system. For engine check connector locations, see Figure. Connector terminals are marked on inside of check connector cover.
Trigger injector for 15 seconds. Measure volume and check spray pattern. Test each injector 2-3 times. Replace injector if volume is not 2.9-3.6 cu. in. (47-59 cc). Maximum difference between each injector is .3 cu. in. (5 cc).
Disconnect injector trigger. Fuel leakage from end of injector should be one drop or less in one minute. Replace injector if leakage is more than specified.

Fig 1: Fuel Injector Spray Pattern Test

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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 Injectors