How To Diagnose A Failing Fuel Injector

If your car is having drivability issues, it can often be frustrating. The complexities of a combustion engine can be a bit daunting to attempt to diagnose. Thankfully our team came up with this helpful guide so you can identify a failing fuel injector. A good tip for any combustion engine is that it needs three main things to run: air, fuel, and spark. If you’ve already ensured you have proper airflow and proper spark, read on as we look at modern fuel injection systems and the injectors themselves.

What Are Some Symptoms Of A Failing Injector?

Fuel injector OEM ford

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When an injector begins to fail, it will be pretty evident during regular operation. A fuel injector uses an electronic signal to spray a specific amount of fuel at a particular time interval - learn more about their basic operation here. When one injector fails, it may be spraying too much or too little fuel for the cylinder. If an injector is beginning to fail, your engine may begin making new noises or suddenly have a different rhythm. Some signs of a failing fuel injector include:

  • Engine Misfire
  • Rough Idle
  • Tachometer begins to “bounce”
  • Lessened fuel mileage
  • Hard starting

How To Diagnose A Failing Fuel Injector

Remove OEM ford fuel injector

Image Credit: 2CarPros

To find the failed injector, you need to recognize that it can be an electrical or mechanical issue. If your car still has lights and power, it is likely a mechanical issue as these tend to be more common. If your engine has misfired, it will typically cause a check engine light. At this point, you’ll need to run the car as you actively look for the issue by monitoring an OBDII scanner.

If you have an OBDII scanner, plug it into your car and read through these codes. Most injector issues are commonly P0300 - P0308 codes. You can clear the codes for the time being, as running the car will bring up more OBD error codes. Now, turn on the vehicle and allow the engine to run; you should actively monitor for a single-cylinder repeatedly misfiring. A single-cylinder that shows an error repeatedly will tell you the corresponding injector has failed. You should double-check that the spark plug for that cylinder is in good operating condition.

If your Ford has a failed injector, check out our inventory of OEM fuel injectors.

Blue Springs Ford Parts has been in business for more than 30 years, so you can be confident in our OEM quality parts. We offer free shipping on orders over $99, and you can order via the phone at 1-800-248-7760.