The Ultimate Fuel Injectors Buying Guide

Guide To Buy Fuel Injectors

While driving the car on the road, the user only pushes the gas pedal to increase the speed of the vehicle, but there are injectors that spray the fuel at its precise timing to develop the required power. Fuel injectors are a very important part of the fuel delivery system as they spray fuel in the combustion chamber. The quick response from the fuel injector is essential when driving on busy roads or highways, whether you have a sedan, SUV, or heavy-duty truck.

What Type Of Fuel Injector Should I Choose?

Depending on the make and model of the car, and the size and position of the fuel injector, there are two major types of fuel injectors available in the market. These fuel injectors differ in performance, price, durability, lifespan, and construction. Injectors are used on diesel and petrol vehicles and come in a variety of sizes. Each is made for different vehicles and has its own performance. Replacing an injector that is too small can cause engine damage from detonation. Replacing an injector that is too big can reduce power at small throttle openings and create idle problems. Therefore, it is necessary to fit the recommended new fuel injector into the vehicle.

There are 2 kinds of injectors in an exceeding diesel injection system. It can be mechanical or electronic. These are categorized as relying on how the fuel is injected within the system. Gasoline vehicles have one kind that's electronic fuel injectors.

Mechanical fuel injectors


Early mechanical fuel systems relied on a sophisticated fuel pump that will give pulses of hard-hitting fuel to the injector feeding every cylinder - and also the pressure of the fuel inbound at the injector would cause it to open, spraying fuel into the combustion chamber or intake. This engine-driven pump would feature a series of pistons, operated by cams, which might generate the burst of fuel needed. Outside of regulation, the output from every piston, few changes to the mixture might be created. Consequently, the mixture was usually not ideal for the engine's load or operative conditions.

Electronic fuel injectors


An electronic fuel injector has electronic management. Its camshaft-driven delivery of pressurized fuel together with the management of the timing of the internal operation by an engine control unit permits electronic unit injectors to attain bound advantages over standard unit injectors Electronic system permits for very precise management over what proportion of fuel is sprayed into the cylinders. The fuel pressure regulator is aware of what proportion of fuel to let through to the injectors via proof from the mass airflow sensing element (MAF). This sensing element tracks what proportion of air is coming into the engine at any given time.

These injectors can receive fuel in the following ways:

A. Top-Feed Injectors: The difference lies in the fuel delivery "feed" to the injector. A top feed injector receives its fuel from the top of the injectors, where the injector top plugs into a fuel rail.

B. Side-Feed Injectors: The side feed injector gets its fuel from the side of the injector where the injector is fitted in a fuel rail.

C. Throttle Body Injectors: A TBI system is the same as a carburetor, in that one or two injectors are in a central throttle body that provides fuel to the engine from the intake manifold. Injectors are fitted directly within the throttle body.

What Are The Types Of Fuel Injection Systems That Require Injectors?

Single-Point Or Throttle-Body Injection


The simple type of fuel injection is the single-point, it replaces the carburetor with one or two fuel injector nozzles that are fitted in the throttle body, that is the throat of the engine’s air intake manifold. For a few carmakers, the single-point injection was a start to the more complicated multi-point system. Though not as precise as the systems that have followed, TBI meters fuel with better control than a carburetor and are less expensive and easier to service.

Pros: The switch from carburetor to fuel injection was made with less amount of disruption to the engine peripherals. Components such as the fuel pipes, air cleaner, fuel pump, and even the intake manifold could remain unchanged.

Cons: The downsides of SPI are plain: The manifold design was compromised in the sense that all the runners had to converge in one place, fuel metering could not be adjusted to meet the intake strokes of single cylinders, and atomization, owing to the less fuel pressure, was poor, and was expensive.

Port Or Multi-point Fuel Injection


Multi-point fuel injection system -(MPFI) has a separate injector for every cylinder, right outside its intake port that is why the system is typically known as port injection. Shooting the fuel vapor this near to the intake port virtually ensures that it'll be drawn fully into the cylinder. The advantage is that MPFI meters fuel more precisely than doing TBI styles, higher achieving the specified air-fuel ratio, and improving all connected aspects. Also, it just about eliminates the likelihood that fuel can condense or collect within the manifold. With TBI and carburetors, the manifold should be designed to conduct the engine’s heat, a measure to vaporize liquid fuel.

Pros: A lot of uniform air-fuel mixture is provided to every cylinder, thus the distinction in power developed in every cylinder is minimum. The vibrations made in MPFI engines are extremely less, because of this lifetime of the engine parts is raised. There is no need to crank the engine twice or thrice just in case of a cold beginning, as happens within the carburetor type.

Cons: Very expensive for some models and needs proper maintenance.

Sequential Fuel Injection Systems


A sequential fuel injection system is known as a sequential port fuel injection system (SPFI) or regular timed injection, it may be a kind of multiport injection. Though' basic MPFI uses multiple injectors, all of them spray their fuel at an equivalent time or in teams. As a result, the fuel could “hang around” a port for as long as a hundred and fifty milliseconds once the engine is idling. This might not appear to be abundant, however, it’s enough of a disadvantage that engineers self-addressed it. A sequential fuel injection system triggers every injector nozzle separately. Timed like spark plugs, they spray the fuel right away before or as their valve opens. It appears like a minor step, however, potency and emissions enhancements are available in extremely little doses.

Pros: Sequential fuel injection operates every injector nozzle independently. They spray the fuel immediately before or as their intake valve opens.

Cons: The potency and emission enhancements are available in exceptionally little doses

Direct Injection


The direct injection takes the fuel injection system idea to a consecutive level, the fuel is directly injected within the combustion chambers, past the valves. The direct injection system that is usually used in diesel engines, is now also used in petrol engines, generally known as DIG for direct-injection gasoline. The fuel metering is precise in modern direct injection systems as it allows the engineers to vary the fuel flow and the process of combustion within the engine cylinders. The science of engine style scrutinizes, however the air-fuel mixture swirls around within the cylinders and the way the explosion travels from the ignition point.

Pros: It improves mileage through a stratified charge engine method. It produces lower emissions and prevents engine detonation/knocking.

Cons: Direct injection systems do price additionally, because the injectors need a lot of higher pressures, and are exposed to the pains of combustion.

What Are The Factors I Should Consider Before Buying New Fuel Injectors?

Depending on the vehicle you drive, the right fuel injectors must be installed so as to provide maximum performance and better mileage. The fuel injection process is important for the combustion and emission formation in the engine. As the fuel is injected, the fuel injector should atomize and vaporize it. The emission formation has to be kept to a minimum level during the combustion. Choosing the wrong fuel injector can have many consequences. Therefore, the following factors must be considered while purchasing a new fuel injector.

A. Length Of Injector 

Replacing an injector that is too small can cause engine damage from detonation. Replacing an injector that is too big can reduce power at small throttle openings and create idle problems. Therefore, it is necessary to fit the recommended fuel injector into the vehicle.

B. Emissions

If the fuel which is injected from the injector doesn’t burn completely, there is a possibility of white smoke coming out from the tailpipe. In such conditions, the timing of the engine should be checked.

C. Timing

The fuel injector should spray the fuel at a proper time, and if failing to do so can create performance issues. To avoid this the injector should be calibrated properly.

D. The Angle of Spray 

The angle of the spray from the injector should be proper for the combustion of the fuel. The angle could change due to the carbon deposit on the injector. For this, special injector cleaners should be used.

E. Heat 

The fuel injectors should be capable of handling the high temperature of the engine. A good brand of the injector is always tested for this.

Which popular Brand Fuel Injector Should I Choose?

Bosch Fuel Injector

Bosch fuel injectors are one of the most demandable brands in the market at present conditions. Backed by superior materials and rigorous testing, Bosch fuel injectors deliver the reliable performance you can count on.

GDI Part numbers: 62855, 62804, 62809, 62807, 62805, 62814, and many more.

GDI Features:

  • OE supplier provides exact flow and original spray pattern for optimal performance.
  • Enhances homogeneous and lean-burn combustion.
  • A key enabler for engine downsizing, while maintaining the desired horsepower.
  • High-pressure fuel is injected directly into the combustion chamber.
  • Maintains new-car smoothness and drivability.
  • Backed by Bosch Limited Lifetime Warranty.

PFI Part numbers: 62391, 62405, 62253, 62640, 62244, 62399, and many more.

PFI Features:

  • Guaranteed OE fit, form, and function.
  • Provides precision flow and original spray pattern for optimal performance.
  • Manufactured of the highest quality materials.
  • The product includes a top and bottom mounting o-ring.
  • Maintains new-car smoothness and drivability.

For more information and detailed product lines, visit Bosch Fuel Injectors Section. 

Delphi Fuel Injector

Delphi fuel injectors aren’t just high quality, they’re Delphi quality. The company has over 100 years of under-the-hood experience for every part they make, due to which they deliver 100% satisfaction for you and your customers.

Part number: 6760301, Fj10594, Fj10566, Fj10049, Fj10066 and more.

Features For Electronic Injectors:

  • These injectors have high-speed dual valve operation for accurate control of injection events.
  • High-pressure injection for optimized combustion and reduced after treatment.
  • Lightweight, compact design for enhanced efficiency.
  • Available with a wide range of high-pressure nozzle options.
  • Multiple injection capability with programmable shot-to-shot injection control.
  • Programmable variable nozzle opening and closing pressure.
  • On-board diagnostic and dynamic trimming capability. (glitch control)
  • Cost-effective technology.
  • Proven reliability and durability.
  • Target emissions: Euro IV, V, and VI; US 07 and US 10 and beyond.

 For more information and detailed product lines, visit Delphi Fuel Injectors Section.

Autoline Products LTD.

Autoline Products LTD. produces parts that meet or exceed OEM standards while providing additional benefits to make sure that the product lasts longer and performs better so you can drive the vehicle with confidence. Using punishing durability testing, they check every new component to ensure you get better performance you can trust.

Part Number: 16-902N, 16-602N, 16-618N,16-2017N and more.


  • Provides precision flow and original spray pattern for optimal performance.
  • Manufactured of the highest quality materials.
  • Proven reliability and durability.
  • Guaranteed OE fit, form, and function.
  • Cost-effective technology.

For more information and detailed product lines, visit Autoline Products LTD Fuel Injectors Section.

Blue Streak (Hygrade Motor)

Blue streak gives technicians the edge by innovating every injector’s component. Blue streak engineers focus on making their parts faster and easier to install and engineer them to provide a longer service life. Using punishing durability testing, they validate every new design to ensure you get the performance you can trust.

Part number: Fj1175, Fj173, Fj817, Fj475, Fj927NX, Fj315, Fj612, Fj713 and many more.


  • Our advanced flow matched injectors promote smooth engine operation and balanced fuel delivery, reducing overall fuel consumption and harmful emissions
  • Stainless-steel calibration slide and spring assembly prevent corrosion within the fuel control body leading to extended service life.
  • Precision wound and trimmed solenoid windings allow the computer to command efficient delivery of fuel.
  • High-temp Viton o-rings enable prolonged sealing of the injector under extreme heat conditions.
  • Fiber optic yttrium aluminum garnet ‘YAG’ laser welding and 100 million cycle testing ensure quality in every box.
  • With industry-leading expertise, when original equipment fails, our products are designed to fix the inherent failure issues.
  • As a global manufacturer, we have complete control of the manufacturing process from componentry to finished product.
  • Electro discharge machining ensures the perfect fit and performance on every application.

For more information and detailed product lines, visit the Blue streak (Hygrade Motor) Fuel Injector Section.

How Long Do Fuel Injectors Last?

Every time you start your car, the fuel injector comes into operation to provide the engine with the required fuel. The fuel injectors are very important components of the engine and a damaged injector will not provide a proper amount of fuel. The very last thing that you just wish to try is to ignore the warning signs on the dashboard stating that the fuel injectors need to be replaced due to damage. The fuel injectors on the car can be operational between 50,000 and 100,000 miles and, if properly maintained, can be more. How long an injector will last majorly depends on what type of gas is used in the car and how often the fuel filter is changed. Using fuel of lower grade can lead to the fuel injectors becoming glued up.

What Are the Symptoms Of Faulty Fuel Injector?

With the advancement in automobile technology, the fuel injector has made its place from the intake manifold to the combustion chamber. The technology has made the injectors more exact in dispensing the fuel. If this precision system has a functional problem such as electrical problems or fuel problems, it can cause drivability issues. Engine credibility is significantly hampered when fuel injectors fail. The fuel injectors are responsible for delivering fuel to the engine of the car. So, when the fuel injection system fails, the engine fails and you may no longer travel. The reasons fuel injectors fail vary, but here are symptoms of a worn-out fuel injector.



A restriction of only 8% to 10% in a single fuel injector can lean out the fuel mixture and cause a misfire. When this happens, the O2 sensor reads lean mixture due to unburned oxygen entering the exhaust system. Carbon deposits can block the injector nozzle, which increases the restriction for the fuel to be sprayed.

Turbo Troubles

Dirty injectors in turbocharged engines can have a dangerous leaning effect which will lead to engine detonation. When the engine is running at higher rpm, it needs all the fuel the injectors can deliver. If the injectors are dirty, there is a possibility of the fuel mixture leaning out, causing detonation. This can lead to turbo failure and higher exhaust temperatures.

Heat Soak


When the engine is switched off, the injectors undergo a heat soak. The fuel evaporates from the injector nozzles and the waxy olefin is left behind. There is no cooling airflow moving through the ports because the engine is off and no fuel flowing through the injectors to clean it away, so due to the heat, the olefins turn into hard varnish deposits. Over time, these deposits clog the injectors. 

Not Enough Resistance

Excessive resistance, open circuit, or shorts in the injector solenoid can cause big problems. The solenoid creates a magnetic field that pulls up the injector pintle. The magnetic field should be strong to lift the spring pressure and fuel pressure above the pintle, If not the injector will not open.

Longer Crank Times

The fuel rail can lose pressure due to an injector leak. Longer cranking time will be required because the rail will need extra time to pressurize.

Misfire Codes


The check engine light can be turned on if there is a misfire code due to a lean mixture. The code is always a P0300 random misfire code or could be misfire codes for individual cylinders, depending on which injectors are most affected.

Lack Of Maintenance

If there are no regular check-ups for oil changes and filter replacements, there are more chances that the fuel injectors will suffer. For port fuel injection, engine oil, which is not changed, results in blowby and a compromised PCV system, which creates contaminates on the tip of the injector.

Loss Of Engine Power


If there is fuel injector failure, there is a sure loss of engine power. The fuel supply will be irregular if the fuel injector is clogged. When the fuel level changes, rather than slow and gradual movements, the low and high rpm's will cause the engine to move in surges.

Clogged Fuel Injector

A clogged injector tries to dispense fuel to the engine, It can even miss supplying the fuel completely and the engine will misfire. When the engine misfires, the engine will start to overheat and will pre-ignite the fuel mixture.

Reduced Fuel Efficiency


Reduced fuel efficiency can be a sign of a damaged fuel injector. A damaged injector can cause fuel to be wasted by leaking from the body.

How Much Does It Cost For New Fuel Injector?

Once you have completed the inspections and are sure that you need to replace your fuel injectors, it is time to replace the injectors as per the manufacturer's recommendation. You have an option to choose from a different brand or the same brand if it suits your budget. The prices range is different and also varies from one brand to the other. Depending on the vehicle you drive, the fuel injector replacement will cost you around $700 to $1,500. While the labor cost is only about $200 to $250. All fuel injectors are individual components but are manufactured to work together. It means, if one injector is not working or is damaged, you will need to change for all of them. 

Bosch Fuel Injectors - Part Number Catalog


Part Numbers

New Injectors  GDI

62811, 62800, 62812, 62806, 62836

New Injectors  PFI

62408, 62386, 62258, 62650, 62400, 62675, 62243, 62688, 62266, 62393, 62643, 62811, 62659


0986435504, 0986435398, 0986435409, 0986435520, 0986435518, 0986435128, 0986435359, 0986435505, 0986435355, 0986435502, 0986435521, 0986435415

Delphi Fuel Injectors - Part Number Catalog


Part Numbers


EX631045, EX631064, EX63803AD, EX633089, EX63801AB, EX63804AE, EX631046, EX635072, EX631054, EX631041, EX636692, EX631047

Autoline Products LTD Fuel Injectors - Part Number Catalog


Part Numbers


16-980, 16-581, 16-994, 16-563, 16-176, 16-525, 16-9040, 16-559, 16-553, 16-1120, 16-531, 16-532

Blue streak (Hygrade Motor) Fuel Injectors - Part Number Catalog


Part Numbers

New Injectors  

Fj732, Fj1166, Fj466, Fj1029, Fj461, Fj258, Fj660, Fj785, Fj1286, Fj319, Fj454, Fj593, Fj224


FI927, FI738, FI495, FI932, FI928, FI933, FI960, FI596, FI489, FI595, FI961, FI962


The fuel injector cleaning doesn't cost too much, it is around $60 and $75. Auto mechanics perform this type of work frequently and it doesn't take more than an hour to complete the job.

After using an injector cleaner, you can expect to see a better running engine. If you are having an engine problem, then it's better to try with an injector cleaner

Driving the car for a long time with a faulty or clogged fuel injector can surely cause problems. The problems can be like high gas consumption, too much smoke from the tailpipe and emissions, rough idle, and jerks while accelerating.

Replacing a fuel injector can be a tough job, but with a little experience, it can be done to save serious money. For fuel injection work mechanics charge a huge amount. If you have the knowledge then the job can be done at home.

A single defective injector is most of the time the cause of an entire engine failure. It may get defective due to debris presented in the fuel which means the other fuel injectors may have started to worn out. This is why it is often best to replace multiple injectors at once.

The major reason for fuel injectors to fail is when debris or rust gets into the fuel system and, after some time it plugs up the nozzle or the nozzle needle gets stuck. Due to this reason, the fuel injector does not perform properly.

John Framigllia
Technical Writer
Our technical writer is known for simplifying automotive parts and services. Intuitive with various vehicles and manufacturers, he knows how to simplify complicated problems.