Warning Signs Of A Bad Fuel Injector | Sun Devil Auto

Bad Fuel Injector?

Combustible engines require three vital elements to help the engine to create power: air, spark, and fuel. If either of these elements isn’t present, your engine will struggle to function or even start. Fuel injection is the process that delivers the fuel to an internal combustion engine. When fuel injectors are clogged or have failed electrically, your vehicle may not perform the way it should. Here’s what you should know about fuel injectors:Person holding vehicle fuel injector

What is a Fuel Injector?

Fuel injectors are simply solenoids, cylindrical coils of wire acting as a magnet carrying an electrical current, that actuate pistons very quickly as part of the engine’s fuel delivery system. It receives and sprays a high-pressure mist of gasoline into the engine as controlled by the car’s internal computer. The computer regulates the amount of fuel and precise timing for fuel to be dispelled. Most cars and light trucks with internal combustion engines are equipped with one fuel injector per cylinder. Over the course of the vehicle’s life, the injectors could fire millions of times!

In the past, vehicles were manufactured to spray fuel into the upper intake manifold to mix with air before entering the combustion chamber for ignition. As time progressed, manufacturers changed to fuel injection using the one injector per cylinder process, where fuel is injected into the lower intake manifold just behind the intake valve. As of late, many vehicle makers have transitioned into direct injection. Direct injection deposits fuel directly into each cylinder instead of the intake manifold. Direct fuel injection systems produce fewer emissions, are more powerful, and deliver fuel more efficiently. However, direct injection does come at a higher cost due to costlier parts and higher fuel consumption. So, while the vehicle may use fuel more efficiently, it does consume a considerable amount.

What are the Signs of a Bad Fuel Injector?

Fuel injectors typically fail due to a buildup of contaminants such as carbon. Carbon build-up can cause a clogged or partially clogged injector, preventing the injector from closing all the way. This results in a drip that creates a misfire. Fuel injectors can also leak externally as a result of dry, cracked rubber seals, or cracks within the injector itself. Electrical portions of the injector are particularly vulnerable to age, heat, and damage from moisture. Symptoms of failure include:

  • Misfires due to a shortage of fuel – Misfires are noticeable events that occur when the engine is running that are often detected by a difference in performance or a subtle popping sound. However, the bigger the engine, the less you’re likely to feel a misfire.
  • Rough idling – You may feel like the engine is going to stall when you stop.
  • Lack of power – The engine is unable to produce an adequate amount of power to run.
  • Poor fuel efficiency – Fuel is wasted either by leaking away, supplying too much or is unable to produce a proper spray pattern to burn.
  • Check engine light on – Too much or not enough fuel delivered to the engine may trigger the check engine light.
  • Struggling to start – Too much or not enough fuel is provided to the engine. This can also cause stalling or prevent the engine from starting altogether.
  • Fuel Smell – If an injector is leaking, you may detect a smell of gasoline while running.

Any time your vehicle is experiencing a leak, it should be inspected by a technician right away, especially fuel leaks. Leaking fuel and vapors can ignite under the hood of the vehicle and could start a fire. A clogged injector is not a safety concern, but it does starve the vehicle causing it to run poorly. Prolonged fuel starvation can lead to internal engine damage or damage to the catalytic converter.  Fuel injectors can be inspected and tested to determine if they should be replaced or cleaned.

How to Test Fuel Injectors

An electric balance test for an electronic failure may be possible with the use of a scan tool. A technician will use this device to measure amp resistance on the injectors and test the volts on the wiring harness for electrical errors. If the fuel injector is clogged, a technician may have to remove the injectors and perform a flow test. A flow test will measure the condition and flow rate of your fuel injectors.

Fuel Injector Cleaning Service

A fuel injector cleaning service is like a tune-up for your fuel system that should be performed every 30,000 – 45,000 miles. Once performed, you’ll notice a considerable difference. This service includes cleaning of the pintle needle or ball and seat inside the fuel injector (the needle is what descends to release the fuel and ascends quickly, cutting off fuel dispersal). The service also removes pooled and puddled fuel at the top of the injector while clearing any carbon deposits and improves the atomization of fuel (fuel must be broken into smaller particles, mixed with air, then vaporized for ideal conditions of use in a combustible engine). While this service will improve the function of your injectors, designed to remove small deposits of carbon, it won’t be able to correct a failed injector. The heavy deposits from poor fuel grades and lack of maintenance are considered an injector failure, which will require replacement.

Let Sun Devil Auto Help

Our technicians at Sun Devil Auto have designed a special Four Step Fuel System Cleaning that includes a fuel injector cleaning service and more! This specialty service will help ensure your vehicle is able to produce the right amount of power and get better fuel efficiency. The Four Step Fuel System Cleaning includes:

  • Cleaning injectors
  • Removal of carbon deposits from the throttle body
  • Clean carbon from valves to prevent sticking and ensuring a proper seal
  • Fuel filter replacement to prevent impurities from entering the engine. Note: most newer vehicles may not require this step as this component is part of the fuel pump.
  • Fuel Additive to help reduce moisture within the system making your fuel more efficient. Also helps to maintain injectors and other components within the fuel system.

Help keep your engine running and producing power optimally by ensuring your car’s fuel injectors are clean and operating at their maximum potential. If your vehicle is not performing as well as it once did, schedule an appointment at any of our service centers for the Sun Devil Auto Four Step Fuel System Cleaning today!