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How-to » Engine » Fuel & Ignition » How to Replace a Fuel Injector
 Note: This is a general guide for all vehicles.

How to Replace a Fuel Injector

  • Fuel Injector
  • Fuel Injector Tester
  • Needle Nose Pliers
Safety Tip:
Always wear safety glasses when working on your vehicle. Wear other personal protective equipment (PPE) when necessary, for example latex gloves or closed toe shoes.

Open the hood and locate the fuel injector rails.
Hook up the fuel injector tester to the Schrader valve on the fuel line.
Turn the key to the ON position and allow the fuel pump to build pressure in the system. Do NOT start the vehicle.
Press the test button on the fuel injector tester and allow it to pulsate the fuel injector for the needed amount of time.
Repeat this for each fuel injector and write down the pressure indicated on the tester for each fuel injector.
After all the fuel injectors have been tested and you have the pressure readings, find the average reading for all the fuel injectors. Add all the readings together, then divide by the number of fuel injectors in the engine.
Compare each original fuel injector PSI reading to the average PSI reading. If you have fuel injectors that are above OR below 1.5 PSI of the average, they are faulty and will need replacement.
After you have determined which fuel injectors need to be replaced, follow instructions on removal and replacement.
Locate and disconnect the fuel pump relay. Start the vehicle to discharge any fuel already in the lines. This will release the pressure in the lines and allow you to remove the fuel injectors safely.
Locate the fuel rail connector. There are a few screws that hold the rail to the engine block. Loosen these screws so that you can pull the fuel injectors out while attached to the rail.
With the fuel injectors and rail disconnected from the engine block, unclip the electrical connector to the faulty fuel injector and replace the fuel injector with a new part.
After all faulty fuel injectors have been replaced, reconnect the fuel rail to the block and road test the vehicle to confirm that the rough running engine has been fixed.
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