Fuel Injector Problems and Symptoms

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Fuel injectors are a marvel of modern engineering making cars more fuel-efficient whilst reducing the harm that is caused to the environment. Your injectors play a key part in the smooth running of your engine delivering fuel exactly when it is needed to optimise performance. Due in part to the technicality of a car engine and the importance of fuel injectors many drivers are put off from getting stuck in and diagnosing problems themselves.

We’ve put together this guide to instil in you the confidence to diagnose a fuel injector problem by spotting common symptoms and resolving it with some basic diagnostic tests. Not only will you be able to diagnose the problem but you’ll also save money at the same time by not having to take your car to a professional mechanic.

Common Injector Problems

We’ve highlighted some of the most common injector problems below, many of which are easy to resolve. However, in others you will be required to replace the fuel injectors.
  • Clogged Fuel Injectors
A clogged fuel injector is unable to successfully supply fuel to the intake manifold. Fuel injectors can become clogged due to the build-up of rust which often arrives through the fuel rail or fuel supply line. Often rust is the result of poor maintenance when your car is in an idle state.

  • Dirty Fuel Injectors
If your fuel injectors are dirty this can lead to a weak or inconsistent spray of fuel inhibiting engine performance. Injectors are subjected to rapid and repetitive movement which generates substantial heat. In result, any fuel additives that don’t spray into the manifold can leave a residue that forms a crust when burnt.
  • Fuel Injector Leaks
Leaking fuel into your engine system when it is not needed can be caused through a faulty part in the injector. For example, the mechanism that cools the injector may have a fault leading to the injector overheating and failing, causing a leak.
  • Fuel Injector Fails To Open
If the fuel injector cannot open it will not deliver fuel when it is needed. Often, if an injector cannot open it is due to faulty windings arising from overheating, a short out or a break. If the fuel injector doesn’t open and there doesn’t appear to be an issue with the windings the fault may be due to a build-up of rust.
  • Fuel Injector Fails To Close
If a fuel injector cannot close when required over delivery of fuel into the engine system can occur. This problem can arise through a faulty spring but also poor maintenance as rust or additives have built preventing the injector from functioning properly.

Fuel Injector Symptoms

As with many car-related problems you will often notice an issue or something behaving differently that will alert you to check a particular part is in correct working order. We’ve outlined some of the most common symptoms that will give you a heads up to check your fuel injectors for a problem.

  • Strong Fuel Smell
One of the tell-tale signs of an injector problem is the smell of fuel. This can be attributed to an injector that is over supplying fuel as it cannot close or a leak in the injector due to a faulty part.
  • Poor Mileage
If your injectors are delivering fuel inefficiently your mileage will inevitably reduce. As with the smell of fuel this can be attributed to an injector that cannot close or leaks.
  • Engine Doesn’t Idle Smoothly
If you notice that your engine is idling unevenly this can be due to a dirty fuel injector, which is delivering an uneven and inconsistent supply of fuel.
  • Inconsistent Engine Power
If you notice fluctuations with the RPM gauge on your dashboard there may be issues with your fuel supply. This can be attributed to a dirty fuel injector.
  • Engine is Misfiring
If your engine is receiving an insufficient amount of fuel it is likely to misfire. If you are noticing engine misfiring issues this can be down to dirty or clogged fuel injectors or an injector that fails to open

Fuel Injector Inspection

The most common causes of injector problems are poor maintenance and general wear and tear of the injectors in your vehicle. Pop some protective gloves on and detach the fuel rails and then each injector in turn from the rail. Once the injectors have been removed inspect them for any rust build-up, cracks or damage and replace if necessary.
We are a UK leading supplier of quality used injector replacements for all makes and models. Our range of injectors are tested and come with a 90 day peace of mind warranty. Best of all, by choosing us you can save up to 90% vs buying new.

Get the injector you need now and get it delivered fast!
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