Fuel Injector: Testing and Inspection

On-Vehicle Inspection





1. Using sound scope or such, check operating sound of injector when engine is running or cranking. Cycle of operating sound should vary according to engine speed. If no sound or an unusual sound is heard, check injector circuit (wire or coupler) or injector.





2. Disconnect coupler from injector, connect ohmmeter between terminals of injector and check resistance.

Resistance of injector: 12.0 - 16.0 ohms

If resistance is out of specification, replace.
3. Connect coupler to injector securely.

Off-Vehicle Inspection

WARNING: As fuel is injected in this inspection, perform in a well ventilated area and away from open flames. Use special care to prevent sparking when connecting and disconnecting test lead to and from battery.





1. Install injector and fuel pressure regulator to special tool (injector checking tool).
Special Tool: (A): 09912 - 58421
2. Connect special tools (hoses and attachment) to pipes of vehicle.
Special Tool: (B): 09912 - 58431, (C): 09919 - 46010
3. Connect special tool (test lead) to injector.
Special Tool: (D): 09930 - 88530





4. Install suitable vinyl tube onto injector nozzle to prevent fuel from splashing out when injecting.
5. Put graduated cylinder under injector as shown.
6. Disconnect coupler from fuel pump relay.
7. To operate fuel pump and apply fuel pressure to injector, using wire. connect two terminals of relay box as shown in figure.

CAUTION: Check to make sure that connection is made between correct terminals. Wrong connection can cause damage to ECM, wire harness, etc.

8. Apply battery voltage to injector for 15 seconds and measure injected fuel volume with graduated cylinder. Test each injector two or three times. If not within specification, replace injector.

Injected fuel volume:
44 - 54 cc/15 sec. (1.49 - 1.83 oz/15 sec.)





9. Check fuel leakage from injector nozzle. Do not operate injector for this check (but fuel pump should be at work). If fuel leaks more than following specifications, replace.

Fuel leakage: Less than 1 drop/min.