Fuel Injector Test
Audible Fuel Injector
Test Light Probe Injector Wiring Step 3 - While the test light clamp is on the positive side of the battery, move the test light probe to the opposite wire in the injector connector, have a helper start or crank the engine while observing the light, when cranking or under load the light will flash brightly, when idling or easy throttle the light will flash more dimly. This trigger circuit for the injector is supplied by the computer and follows the throttle and engine demand. If these test revealed that there was no pulse and the computer has power and not generating a fuel injector trigger signal suspect a crank angle sensor, (engine not running) or shorted computer or sensor. A shorted injector can hinder the injector driver operation for additional injectors, unplug all injectors and re-test pulse trigger, if pulse returns, plug the injectors back in one at a time until the pulse fails, replace the shorted injector. If tests check okay, proceed to next step.
Test Light Flash Step 4 - A voltmeter is used in this test, adjust the meter to the ohms setting, these next steps can be performed with the injector installed or uninstalled.
Multi Volt Meter Set To Ohms Step 5 - Identify the injector to be tested and inspect for defects or bad connections.