What causes a fuel injector to stop working? How can you tell if it isn’t working? If you’re not getting the performance you expect out of your engine, it might be due to a faulty fuel injector. It’s actually a very common issue, and can dramatically affect how your vehicle operates.

Here’s a closer look at how to know if your fuel injector stops working:

  • Your engine has lost power: Your fuel injector delivers the fuel and air the engine needs to combust. If you’re not getting enough power, it could be a sign of a faulty fuel injector.
  • Bad fuel economy: Not getting the mileage you used to? Your fuel injector could be the cause. It may be wasting or leaking fuel.
  • Problems with idling: Experiencing a lot of roughness and vibration while idling could mean you’re having fuel injector issues.
  • Misfiring: Misfires are pretty noticeable. You may hear knocking in the engine (pre-ignition) or notice overheating. These can occur because of failed fuel injectors.

Why do fuel injectors stop working?

Here are some of the most common reasons your fuel injectors stop working:

  • Poor fuel quality: When your fuel has too many impurities, it will clog up your fuel injectors. That makes it much harder to deliver enough fuel to the engine. Always use the highest quality fuel you can afford to avoid this problem.
  • Engine blow-by: Fuel and oil residue can blow past the pistons and the crankshaft during compression. If the air filter doesn’t catch the sludge, it can clog up your fuel injectors.
  • Broken fuel injector: Your fuel injector may also just break. They can crack or spring a leak, which means they can’t deliver air and fuel to the engine properly. You’ll probably need to replace the fuel injector entirely.
  • Solenoid failure: Solenoids create a magnetic field, which pulls up the fuel injector pintle. If the solenoid fails, it won’t create the magnetic field and could cause the entire injector to fail.
  • Heat soak: Finally, heat soak may be a problem. This occurs when fuel residue evaporates in the fuel injector nozzles, after you’ve shut off your engine. The residue becomes waxy, and there’s no mechanism to flush it out after the engine is shut off. Eventually, the waxy residue builds up enough that it clogs the fuel injectors. Keep in mind that fuel has detergents to solve the problem—but if you’re only taking short trips, you won’t have enough time to clean out the nozzles.

Now that you know how to tell if your fuel injector isn’t working, you’ll be prepared to take your vehicle in to the repair shop at the first sign of trouble. As always, the sooner you can address potential problems, the less time and expense it will require to address. Keep an eye out for these signs, then visit or call Coastal Diesel Injection to schedule a repair appointment. We’ll make sure your fuel injectors are performing perfectly. Reach out today—we look forward to assisting you soon!