How to Test Fuel Injectors

You start your car and notice an odd sound. Maybe even a lack of a sound. Your car is misfiring and one of the top culprits may be your fuel injectors. Instead of wasting money having the mechanic find the problem, test the injectors yourself with an ohmmeter or multimeter and a screwdriver. This can save you time and money.

Instructions

Testing With a Multimeter/Ohmreader

1

Set your multimeter to check for resistance or turn on the ohmmeter.

2

Disconnect the wires to the injector.

3

Place your meter's leads on each of the two injector terminals. Read the meter display.

4

Check your service manual for your car's resistance number. Most fuel injectors have a resistance of between 10 to 18 ohms.

5

Test each injector. If any of the injector readings are higher or lower than they should be, you need to replace them.

Listening

6

Put a long screwdriver directly on the injector while the car is running.

7

Hold the handle up to your ear. You should be able to hear a rhythmic clicking sound. If you do, your injector is good. Hearing a clunk-clunk type noise means you have found your problem.

8

Hearing silence or unusual clicking patterns means either the injector, wires or plunger may be bad or sticking. You will either have to clean or replace them.