The fuel injection system plays a big role in the efficient working of the vehicle. The fuel injection system consists of a fuel pump, fuel rails, fuel injector, and fuel filter. These parts ensure the engine to receive the precise amount of the air-fuel mixture.
When the fuel injectors are clogged, they produce different signs. This article explains the bad fuel injector symptoms, causes, and how to clean a clogged fuel injector.
What is a Fuel Injector?
A fuel injector is a mechanical device that injects fuel into the engine cylinder. The fuel injector contains a spray nozzle that properly injects diesel or petrol into the combustion chamber for optimal efficiency and combustion.
Fuel injectors were introduced as an alternative to older carburetor systems because they help to improve fuel efficiency and reduce emission rates.
However, the fuel injector may produce different problems if not properly maintained.
If the injector is faulty, the fuel will not be injected into the engine all at once, or the intervals at which it must be injected will be changed. In any case, your car doesn’t work according to your requirements.
Working of Fuel Injector
A fuel injector is one of the most vital parts of the internal combustion engine. It ensures the proper supply of fuel to the combustion chamber. The vehicle engine utilizes air and fuel to generate power. A fuel injector works in the following way:
Fir of all, the fuel pump takes fuel from the fuel tank and transfers it to the fuel injector through fuel lines. When the engine control unit senses the fuel requirements, it sends a signal to the fuel injector, and the injector injects fuel into the engine cylinder according to the requirements.
As the fuel is injected, the air is mixed with the fuel, and the combustion process of the air-fuel mixture takes place.
Symptoms of Dirty Fuel Injector
As the fuel injector is clogged or damaged, it produces one of the below-given symptoms:
- Rough Idling or Idle Noise
- Misfiring
- Engine Vibration
- Fuel Leaks
- Check Engine Light Turns On
- Fuel Odor
- Engine Surge
- Bad Fuel Economy
- Hard Starting
- Failed Emissions Test
1) Rough Idling
Rough idling or stalling is one of the main symptoms of a dirty fuel injector. As the injector goes bad, your vehicle noise may change from quiet to an extreme level. The vehicle engine starts rough idling or idle noise due to dust accumulation on the injector nozzle.
The dust accumulation on the injector nozzle affects the amount of spray and fuel spray ability. The engine may also generate rough noise due to dirty air filters, spark plugs, head gaskets, or other parts.
Read More: Causes of Engine Stalling
2) Check Engine Light Illumination
The illumination of the check engine light is one of the major signs of a bad fuel injector. The check engine light is located on the vehicle dashboard. This may illuminate due to many other problems, but a damaged injector is one of them.
Whenever the injector delivers less (and in some cases more) fuel than the requirements of the engine, it can reduce engine efficiency and activate the check engine light. Use the OBD2 scanner to check the problem.
Read More: Check Engine Light Illumination Causes
3) Engine Vibration
The vibration of the vehicle engine is one of the common signs of a dirty or bad fuel injector. A bad injector can cause the corresponding cylinder not to fire. This means the engine will vibrate or belch after trying to complete each cycle without fuel while driving.
4) Misfiring
Dirty injectors can lead to engine misfiring. Due to this problem, the engine feels spattering. In other words, when the engine misfires, the vibration is transmitted to the car. This misfire occurs when the fuel injector doesn’t properly supply the air-fuel mixture to the engine combustion chamber.
5) Engine Surge
The engine surging is one of the most common signs of a dirty fuel injector.
The engine surging occurs when the injector injects more fuel into the engine cylinder than the required amount. This engine surging highly slows down the speed of the engine. In such a situation, you will observe a clear change in engine speed under constant load instead of staying constant.
6) Fuel Odor
This includes fuel leaks, but you can smell gas if the gas isn’t burning because it’s damaged or stuck to the injector. The fuel may also leak due to a damaged fuel line or sensor fault that is telling the engine control unit to inject more fuel than it needs.
In any case, the cause of the gasoline smell should be identified and addressed just before it becomes a serious safety issue.
7) Fuel Leaks
If you smell a pungent and sharp fuel smell in the compartment of your vehicle, then you may have a fuel leak. This fuel may leak due to a damaged or worn fuel injector. The fuel may also leak due to a damaged head gasket, fuel pump, or fuel filter.
8) Bad Fuel Economy
A damaged or dirty fuel injector may also lead to poor fuel economy. This is because the ECU requests more fuel from the injector, but the combustor is not receiving more fuel. When the engine consumes less fuel, then your fuel economy reduces.
When you notice a reduction in your fuel economy, immediately contact a professional mechanic to fix the issue.
9) Failed Emissions Test
If the injection pattern of the fuel injection system changes and the injector injects too much or too little fuel into the combustion chamber, there is a chance that the vehicle will fail the emissions test.
The inefficient and improper injection of the fuel may increase the emission rate of the exhaust gases, and the catalytic converter will not work efficiently.
In a few situations, a fuel injector leak can overconcentrate the air-fuel mixture and ultimately burn out the catalytic converter.
Read More: Bad Catalytic Converter Symptoms and Causes
10) Hard Starting
A faulty or clogged fuel injector may make it challenging for the engine to start, particularly in cold weather. This is because the injector is not delivering the sufficient amount of fuel needed for the engine cylinder to ignite.
Causes of a Bad Fuel Injector
- Dirty fuel: Dirty fuel is one of the major causes of clogged fuel injectors.
- Damaged fuel filters: The fuel filters remove the solid contaminant from the fuel and deliver clean fuel to the injector. As the fuel filter is damaged, they don’t remove solid dirt from the fuel which further leads to the fuel injector blockage.
- Corrosion: Moister or water in the fuel system leads to corrosion on the fuel injector.
- Fuel additives: Specific fuel additives may lead to the failure of the fuel injector.
- Worn parts: The internal parts of the injector may wear out with time which may cause a bad injector.
- Insufficient fuel pressure: Your injector may be damaged due to an insufficient supply of fuel pressure.
Cleaning Cost of Fuel Injector
Fuel injectors don’t last forever, but there are a few tips through that you may extend their life as much as possible. Maximum manufacturers recommend that you should clean the injector every 30,000 miles or so. This will prevent the injector from clogging and injecting fuel into the cylinder.
How to clean Fuel Injectors?
Follow the below-given steps to clean your clogged fuel injector:
- Wear PPES: Before starting the cleaning process, properly wear the required PPEs (such as gloves and safety glasses).
- Find the fuel injector: Locate the location of the injector. The location of the fuel injector varies according to the vehicle model. Read the vehicle manufacturer’s instruction manual to easily find the location of the injector.
- Remove the fuel pump from the fuel injector: Now, find the fuel pump and disconnect its connection to the injector.
- Remove the pressure regulator: Check the vehicle manual to check whether you should perform this step or not. If necessary, just pull the pressure regulator and remove it from the injector.
- Link the fuel port to the cleaning kit: Now locate the fuel port, and connect the cleaning kit. Follow the instruction of the kit to connect the port and hose.
- Disconnect the fuel tank cap: Now, remove the fuel tank cap. This helps to stop the build-up of additional pressure.
- Turn on your car engine: Now, turn on your vehicle engine and wait for at least 4 to 11 minutes for an efficient result of the cleaning solution.
- Disconnect the cleaning kit: Now, remove the cleaning kit from the vehicle and reinstall the fuel pump and pressure regulator.
- Turn on the car engine: Now run the vehicle and check the result.
FAQ Section
What is the replacement cost of the fuel injector?
The replacement cost of a fuel injector depends on the area you live, labor cost, vehicle model, and type of brand. The average replacement cost of a new fuel injector is from $90 to $510. The fuel injector cost is from $60 to $310, while the labor cost is from $30 to 200$.
What are the signs of a bad fuel injector?
The signs of the bad fuel injector are given below:
- Failed emissions test
- Rough idling or idle noise
- Bad fuel economy
- Engine misfiring
- Engine surge
- Engine vibration
- Fuel leaks
- Fuel odor
- Check engine light turns On
What is the function of the fuel injector?
A fuel injector is a mechanical device that is used to inject fuel into the engine cylinder.
Can a fuel injector be repaired?
Yes, the faulty fuel injectors can be repaired in some cases. Depending on the issue, you can repair your faulty injector by fixing electrical connections, replacing internal parts, or cleaning. However, if your injector is badly damaged or worn, it is recommended to replace it.
What chemicals clean fuel injectors?
The following chemicals are most commonly used to clean the fuel injectors:
- Polyisobutylene (PIB)
- Polyetheramine (PEA)
- Polyisobutylene amine (PIBA)
Read More
- Bad Fuel Pump Symptoms and Causes
- Bad Head Gasket Symptoms and Causes
- Bad Oil Pan Symptoms and Causes
- Engine Overheating Causes and Symptoms
- Bad Spark Plug Symptoms and Causes