Fuel Injector: Testing and Inspection

Checking Injector Operation:

1. Inspect injector operation

Check operation sound from each injector.

a. With the engine running or cranking, use a sound scope to check that there is normal operating noise in proportion to engine rpm.

Checking Injector Operation:

b. If you have no sound scope, you can check the injector transmission operation with your finger. If no sound or unusual sound is heard, check the wiring connector, injector or injection signal from the ECM.

Checking Injector Resistance:

2. Inspect injector resistance

a. Disconnect the injector connector.

b. Using an ohmmeter, measure the resistance between the terminals.

Resistance: Approx. 13.8 0hms

If the resistance is not as specified, replace the injector.

c. Reconnect the injector connector.

Adapter Installation:

3. Inspect injector injection

CAUTION: Keep clear of sparks during the test.

Adapter Installation:

a. Disconnect the fuel hose from the fuel filter outlet.

b. Connect union and hose to the fuel filter outlet with two new gaskets and the union bolt.

HINT: Use the vehicle's fuel filter.

Pressure Regulator Hook-up:

c. Remove the pressure regulator.

d. Connect the fuel return hose.

e. Install a new O-ring to the injector.

Injector Hook-up:

f. Connect union and hose to the injector, and hold the injector and union with clamp.

g. Put the injector into the graduated cylinder.

HINT: Install a suitable vinyl hose onto the injector to prevent gasoline from splashing out.

Jumper Installation:

h. Using a jumper wire, connect terminals +B and FP of the data link connector 1.

i. Reconnect the battery negative (-) cable.

j. Turn the ignition switch ON.

NOTICE: Do not start the engine.

Injector Testing:

k. Connect wire to the injector and battery for 15 seconds, and measure the injection volume with a graduated cylinder. Test each injector two or three times.

Volume: 54-64 cc (3.3-3.9 cu in.) per 15 sec.

Difference between each injector: 5 cc (0.3 cu in.) or less

If the ignition volume is not as specified, replace the injector.

Leak Inspection:

4. Inspect leakage

a. In the condition above, disconnect the test probes from the battery and check the fuel leakage from the injector.

Fuel drop: One drop or less per minute