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​5 Symptoms of Bad Diesel Fuel Injectors

Feb 2nd 2022

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Diesel fuel needs to be injected into the combustion chamber, which is why it’s important to maintain your diesel fuel injectors. These powerful devices monitor fuel quality and pressure to maximize power and fuel efficiency. But your diesel fuel injectors won’t last forever. Dirt and other debris can clog the injector heads. They can also crack over time, leading to leaks and wasted fuel. It’s best to either clean or replace your diesel fuel filters on a regular basis or the problem could spread to other parts and components. This could lead to an expensive engine rebuild as you replace your damaged diesel parts.

Don’t wait for your parts to fall apart. Here are five warning signs that your injectors need to be cleaned or replaced:

  • Starting Issues

You’re bound to have trouble starting the engine if your injectors are faulty. The injectors need to fire the correct amount of fuel at the right time in order for the engine to start. You may experience a rough, hard, or false start when turning on the engine as well as the occasional misfire. The fuel could be clogged in the injector head or there may not be enough fuel pressure to start the engine.

  • Poor Fuel Efficiency

When your injectors are working properly, your engine uses every drop of fuel to its maximum potential. But you’ll notice a gradual drop in fuel efficiency as the injectors continue to degrade. Some of your fuel may leak into the crankshaft or the engine may have to use more fuel than normal to generate the same amount of power. Keep track of how often you need to refuel and compare it with the odometer to stay on top of the issue.

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  • The Smell of Fuel

This notable odor is usually a sign that fuel is leaking into the crankshaft. It could be leaking out of the fuel injectors as the seals begin to crack. Watch out for smoke under the hood as the leaking fuel starts to burn.

  • Dirty Exhaust

Your exhaust can tell you a lot about the health of your engine. The engine should burn all the fuel in the combustion chamber. If the injectors are misfiring or the fuel isn’t under the right amount of pressure, some fuel may stay in the combustion chamber. You’ll notice white smoke coming out of the exhaust, which is always a sign that something is wrong.

  • Misfire

Shop for Injection Pressure Regulator (IPR) Valves Online to Improve Fuel Efficiency

Don’t forget to consult your owner’s manual when replacing or cleaning your diesel fuel injectors. If you don’t feel comfortable cleaning or replacing your injectors yourself, contact a local mechanic that can do the job for you. You can always buy your replacement parts online to save money. Keep in mind that most diesel fuel injectors only last around 100,000 miles or 150,000 kilometers.

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Other Possible Causes

If you are running into these issues, you might need to do more than just replace or clean your fuel injectors. There could be other problems with the vehicle’s fuel injection system. For example, the injection pressure regulator (IPR) valve helps adjust fuel pressure based on operating conditions. If this device is malfunctioning, you may runt into some of the same issues as mentioned above. Consider conducting a fuel injector pressure test to find out if there’s an issue with the fuel pressure. If the pressure below or above average, you likely need to replace your IPR valves, especially on the 6.0L engine. You can find replacement 6.0 IPR valves online.

Using dirty or poor-quality fuel will only damage your engine’s fuel injection system. Particulate matter and other harmful deposits will clog the injectors, making it that much harder for them to regulate fuel pressure. Remember to replace your diesel particulate filters according to the manufacturer's recommendations.

Your engine wouldn’t be much good without a functioning fuel injection system. Keep this information in mind to avoid running into problems behind the wheel or you’ll likely spending thousands of dollars on repairs.