This article takes a comprehensive look at fuel injector repair, symptoms, and costs to repair, clean, or replace a bad fuel injector.

Of the vast majority of automobiles’ advancements in the 20th century, the change made to automobiles engines ranks as one of the most important.

That change, which centers on carburetors’ substitution with electronic fuel injectors in engines, first made its way into automobiles’ engines in the late 1960s. 

As the benefits of this newly introduced fuel injection method dawned on automobile giants, the use of fuel injector instead of the conventional carburetor began surging until it finally exited the carburetor in the 1990s. 

While the benefits of fuel injector led to it becoming the conventional fuel injection method in engines, it also came with its truckload of mechanical issues. 

For vehicle owners who frequently clean their vehicle’s fuel injectors, the mechanical issues common to fuel injectors may not occur as such.

But, as with any mechanical components of vehicles, a vehicle’s fuel injector may either fail, get clogged, and may need to be replaced. 

That can be challenging, and as a result, MotorsTell presents the various symptoms to look out for that indicate a faulty fuel injector.

To fully understand these symptoms, it’s best we briefly expatiate on how a fuel injector works in an engine.

How Does Fuel Injector Work?

A fuel injector supplies just the right amount of fuel required into the engine’s cylinder through a small nozzle at very high pressure.

The supply of fuel by the fuel injector makes internal combustion in an engine possible.

To ensure the process goes smoothly, the fuel injector has to be very precise. 

The fuel injector has to supply fuel at the right angle, the right amount, right pressure, and right spray pattern.

The design of the fuel injector makes it possible for fuel to be supplied only.

The engine’s Engine Control Unit (ECU), best described as the vehicle’s brain, makes precision very possible. 

The ECU ensures that the right amount, pressure, and right air/fuel mixture is channeled to the fuel pump by means of sensors.

The fuel pump is another mechanism in the vehicle’s engine responsible for pushing fuel from the fuel tank, through the fuel line, and into the fuel injector. 

The ECU calculates the right amount of fuel needed to be supplied to the engine, and while the fuel pump does its job, that information is relayed to the fuel injector solenoid, which opens up for the right amount of fuel to be supplied.

What are the Symptoms of a Bad Fuel Injector?

The importance of a good fuel injector to a vehicle’s performance can not be overemphasized.

As a result, when the fuel injector is faulty, the vehicle’s performance would be affected.

The right amount of fuel would not be supplied, thus altering your vehicle’s performance. 

Knowing the symptoms of a faulty fuel injector would alert you to take action and prevent further damage;

below are the various symptoms of a defective fuel injector.

1. Rough Idle or Engine Stalls

The aforementioned is one of the main symptoms of a bad fuel injector.

As a result of an inadequate supply of fuel or no supply of fuel, your vehicle’s RPM would fall below the usual level, causing a violent idle.

It can also cause your vehicle RPM to fall to the extent that your vehicle stops and requires you to restart.

2. Engine Vibration

A faulty fuel injector would bring about engine vibration.

This is due to the engine not being able to fire at the right time or being totally incapable of firing.

The inadequate supply of fuel would cause the engine not to complete its cycle, leading to shaking or vibration. 

3. Engine Misfire

Inadequate supply of fuel to the fuel injector resulting from it being clogged or faulty would lead the to misfire.

That would also make the vehicle struggle with acceleration.

That would be noticeable when attaining high speed or moving up a hill. 

There also would be a slight delay after powering the vehicle by pressing the pedal.

If the fuel injector isn’t fixed, further damage might be done, especially to the engine that may overheat due to the affected air/fuel mixture.

4. “Check Engine” Light Turns On

The “check engine” light (CEL) on your vehicle dashboard turns on for various reasons, including failed mass air flow, oxygen sensors failure, and many other reasons. 

In the case of a faulty fuel injector, when the CEL comes on, it signals that the fuel injector isn’t supplying enough fuel, leading to lowered engine efficiency.

Making use of an On-Board Diagnostics (OBD) 2 scanner can confirm this.

5. Fuel Leak

A broken or cracked fuel injector would interfere with the supply of fuel to the engine.

The fuel would thus leak out of the gasoline pipe.

When you check the fuel injector, you’ll notice fuel on the fuel rails and other exterior parts.

6. Fuel Odour

A consequential effect of fuel leaks, when fuel isn’t being burnt up in the engines and is leaked to the fuel rails and other exterior parts of the engine, you definitely would perceive a potent smell of fuel in your vehicle. 

The issue may not exactly mean a faulty fuel injector.

It could also mean that the fuel lines are faulty, or the Engine Control Unit (ECU) is requesting more than the necessary amount of fuel.

7. Engine Surge

A bad fuel injector can spray more fuel than is necessary to the engine.

That would lead to engine surge, and your vehicle’s acceleration would decrease, negatively affecting your vehicle’s performance. 

The continuous supply of fuel more than necessary to the engine would put the engine under constant load and cause the RPM to change consistently.

8. Large Fuel Intake

Inadequate supply of fuel to the engine would cause the Engine Control Unit to supply more fuel, leading to a large fuel intake that isn’t being used by the engine.

That can result in a low fuel economy.

9. Failed Emission Test

When the fuel injector breaks, it leads to incomplete fuel burn, which would increase emission.

The air/fuel mixture can also be too rich and damaging the catalytic converter, thus, increasing the fuel injector repair cost.

Fuel Injector Repair & Replacement

While most fuel injector issues can be resolved by professional cleaning or replacement of the o-rings, in instances of leaks, fuel injector replacement is inevitable when it cracks or breaks. 

How Much Does a Fuel Injector Cleaning Cost?

Regular cleaning of your vehicle’s fuel injector is recommended to ensure that it lasts longer.

For every 30,000 miles traveled, experts recommend that the fuel injector is cleaned.

A bottle of fuel injector cleaner, which costs between $10 to $15, would do the job.

You can clean your engine’s fuel injector when doing your routine oil change.

A professional fuel injector cleaning would cost more—mechanics charge between $50 to $100 for cleaning.

Your vehicle does not have to be with the mechanic during a professional fuel injector cleaning. 

Some companies allow vehicle owners to ship their fuel injectors. But, that could raise costs by $15 to $20.

It’ll also mean your vehicle would have to lay waiting while they do a thorough job.

How Much Does a Fuel Injector Replacement Cost?

The cost of fuel injector replacement is significantly high.

That is due to the fact that fuel injectors work with other injectors, and when one needs to be replaced, in almost any instance of fuel injector replacement, all the injectors would have to be replaced. 

The fuel injectors replacement cost boils down to the model of your vehicle. Price ranges from $400–$1,500.

To cut costs, you should shop around for the parts to be replaced.

Resorting to Non-Original Equipment Manufacturer (OEM) parts can cut costs.

However, to ensure you get the best value, purchase original manufactured parts.

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