How do fuel injectors work?

Fuel injector generating power.

The best fuel injectors enable an engine to generate maximum power while minimizing fuel consumption and reducing pollution. Fuel injectors with the latest technology help reduce carbon and greenhouse gas emissions by delivering accurate fueling with optimized air mixing. This article outlines what a fuel injector is and how it works in diesel, natural gas, and hydrogen engines as well as in hydrogen fuel cell vehicles. 

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What does a fuel injector do? 

A fuel injector regulates the injection of fuel into an engine’s internal combustion chamber where it is mixed with air and ignited. The combustion chamber is where the chemical energy in diesel, hydrogen, and natural gas is converted into power for the vehicle. When actuated by the electronic control unit (ECU), the injector delivers a precise amount of fuel to ensure efficient combustion. 

How does a diesel injector work? 

A fuel injector in a diesel engine consists of a solenoid (a type of electromagnet), a nozzle, and a needle within the injector body. Modern diesel engines are direct injection, meaning fuel is delivered directly into the combustion chamber.  

In the cylinder, air is compressed by the upward movement of the piston. As the piston nears the top of its path, an electrical signal is sent to the solenoid, causing the injector needle to lift, and allowing high pressure fuel (up to 37,000 psi) to flow through the nozzle and into the combustion chamber to mix with air. Because of the elevated temperature created by the compression stroke, the air-fuel mixture auto-ignites, creating power and driving the engine's pistons.  

The combination of high fuel pressure and exceptionally fine injector nozzle holes ensures optimal mixing of air and fuel to meet even stricter emissions standards. In diesel engines, a fuel injector can fire multiple pulses in a single power stroke which can be used for noise mitigation and emissions control.

How does a natural gas injector work? 

Natural gas engines function similarly to gasoline engines in that their combustion process utilizes a spark plug (unlike diesel engines). Natural gas is compressed and stored in a fuel tank, typically located in the back of the vehicle. The high-pressure gas is routed through a pressure regulator that reduces the pressure of the incoming fuel to an appropriate level to ensure accurate fueling from the injector. An electrical signal opens the injector and ensures the correct volume of fuel is delivered into the intake air stream. That air-fuel mixture is delivered to the combustion chamber where it is ignited by the spark plug, creating power.

Natural gas is a lower carbon-intensity fuel compared to diesel and is considered a critical technology to help fleets reduce carbon emissions today. Natural gas can be leveraged for immediate reduction, and, in the case of Renewable Natural Gas (RNG), it can even possess negative carbon-intensity 

How does a hydrogen ICE injector work? 

Hydrogen engines have a high degree of components common with natural gas and diesel engines. Cummins’ hydrogen engines are built on the cutting-edge fuel agnostic engine platform. Though they share common components, hydrogen engines have specific requirements for regulating and injecting fuel. This is because hydrogen is more flammable than diesel and is easier to ignite in a combustion chamber. Because of this, hydrogen engines can have “pre-ignition” issues, which may cause backfiring. One way to overcome pre-ignition issues is for an engine to use a direct injection system. Direct injection systems introduce hydrogen directly into the cylinders. Cummins is currently developing a 15-liter hydrogen engine that uses direct injection. 

What is the injector system in fuel cell vehicles? 

Hydrogen fuel cell vehicles harness electrical energy produced by splitting a hydrogen atom into protons and electrons and reacting it with oxygen.  On fuel cells, the hydrogen delivery system must provide sufficient fresh flow of hydrogen to the anode side of the fuel cell stack to meet the electrical power demands of the application. This can be accomplished using either a hydrogen injector or proportional valve, both of which accurately regulate the flow of hydrogen to the stack. Unlike diesel, natural gas, and hydrogen internal combustion engines (ICE), fuel cells do not have any carbon or pollutant emissions. The byproducts of splitting a hydrogen atom in a fuel cell are electricity, heat, and water vapor. 

What is the role of fuel injectors in energy transition? 

Fuel injectors are more than just a component in engines. They can play a key role in the energy transition from fossil fuels to cleaner energy sources. By optimizing fuel consumption in traditional diesel engines and facilitating the operation of alternative fuel engines like natural gas, hydrogen internal combustion engines (ICE), and hydrogen fuel cells, fuel injectors contribute to trucking fleets’ efforts to reduce carbon and greenhouse gas emissions.  

Read more about Cummins fuel system products. Cummins stands ready to partner with on-highway and off-highway vehicle fleets to help them get the most out of their engines while achieving sustainability goals. Contact your local Cummins sales office today to learn more.  

Accelera™ by Cummins works on the development of new technologies in fuel cells. Accelera, a business segment of Cummins, is both a components supplier and integrator, focused on batteries, hydrogen fuel cells, e-axles, traction drive and electrolyzers. For more information on the diverse Accelera portfolio of zero-emission solutions please visit accelerazero.com.

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The 15 White Coats Partners with Black Worldschoolers Mobile Bookstore, powered by Cummins, to bring African American literature to Indianapolis Schools

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The RESILIENT READERS BOOK CLUB is a school age book gifting initiative created by the nationally renowned The 15 White Coats and Black Worldschoolers Mobile Bookstore to provide access to high quality Black literature through book boxes placed inside of youth centered organizations. The Indianapolis launch is made possible by global power leader Cummins Inc., through its Cummins Advocating for Racial Equity (CARE) initiative. We are all committed to diversity, equity and inclusion. Moreover, we are committed to making a meaningful and lasting impact in the city of Indianapolis, IN.

Who

In 2019, The 15 White Coats (www.the15whitecoats.org), an internationally recognized non-profit organization whose mission is to diversify medicine through mentorship, literacy accessibility, and economic assistance. The 15 White Coats started after a photo of 15 Tulane School of Medicine African-American medical students posing in front of plantation slave quarters went viral. The organization has helped over 2000 students with over $500,000 in scholarships to help with entering the healthcare field, whether it’s physicians, dentists, PAs, optometrists, NPs, nurses, etc. Moreover, nearly 10,000 15 White Coats photos have been distributed to schools, students, institutions, and businesses worldwide. 

The non-profit has been featured by Good Morning America, NBC Nightly News with Lester Holt, New Orleans Times-Picayune, CNN, MSNBC, NPR, U.S. Today, AAMC, AMA and People Magazine.

Visit their site to learn more. 


Black Worldschoolers Mobile Bookstore is a bookstore on wheels sharing stories that uplift Black life, Black heritage, and Black joy. Described as a "bookstore on wheels with ice cream truck energy” owner, Natalie Pipkin is on a mission to provide access and awareness to Black stories as well as excitement and engagement around reading, Black Worldschoolers Mobile Bookstore debuted as Indiana's first bookstore on wheels June 2022 and is the first of its kind in the region. Since its initial online launch in December 2020, Black Worldschoolers has been a recipient of the Jrue & Lauren Holiday Social Impact Fund, featured in Sports Illustrated, Scripps News, The Indianapolis Star, WFYI, FOX59 and WRTV. 

Visit the Black Worldschoolers site to learn more.


Cummins Inc., is a 104-year-old global power technology leader, with complementary business segments that design, manufacture, distribute and service a broad portfolio of power solutions. Headquartered in Columbus, Indiana (U.S.), since its founding in 1919, Cummins employs approximately 73,600 people and is committed to powering a more prosperous world through three global corporate responsibility priorities critical to healthy communities: education, environment and equality ofopportunity. Cummins has a deeply rooted history in fighting for social justice, serving its communities and living the company’s core values of diversity and inclusion.

In October 2020, Cummins Inc. launched Cummins Advocating for Racial Equity (CARE) so Cummins could take a leading role in the work to dismantle systemic discrimination against the Black community in the U.S. As a first step in this journey, CARE brings together all Cummins' capabilities - its people, its balance sheet and the company’s philanthropy - to drive racial equity and combat the impact of racism on its people, communities, and economy. 

Through CARE, Cummins is taking decisive action to address, and spearhead change throughout targeted CARE communities in the U.S., across four impact areas:

  • Police reform
  • Criminal justice reform
  • Economic empowerment
  • Social justice reform

Through CARE’s efforts, Cummins is dedicated to improving communities in which it operates to have a direct impact on the lives of its employees and its neighbors.

WHY

According to Indiana’s National Assessment Educational Progress (NAEP), only 33% of 4th graders in Indiana read at or above a proficient level, with Black students among those suffering most. The NAEP results reflect the reality of educational inequities created by centuries of systemic racism that are still present today. How do we begin to engage and excite youth in the area of reading? High quality, culturally relevant books that can serve as mirrors and motivation to a historically left out population is a start. The Martindale-Brightwood neighborhood of Indianapolis has a scarcity of books in places where Black children are present and a lack of stories that positively reflect the youth within the communities.

This partnership is created to provide children and families access to enjoyable books, powerful stories and meaningful community interaction that will cultivate, a joy for reading, a healthy sense of self, fruitful lives and future aspirations. We will display boxes containing 15 curated books for K-3rd graders as designed by The 15 White Coats & Black Worldschoolers Mobile Bookstore.

Employees from the Cummins Community Involvement Team (CIT) along with volunteers within partnering organizations will deliver the threetiered book boxes and read stories aloud to the children at site locations throughout the year. Locations in the Martindale-Brightwood community as identified by the Edna Martin Christian Center, Kipp Indy, and other local partners. The partnership will host a literacy event in collaboration with Kipp Indy Schools in Spring 2023 to bring in the Mobile Bookstore and National Book Award Finalist, Author, Derrick Barnes. 

Resilient Readers Book Club is a book gifting initiative for school age children created by the nationally renowned, The 15 White Coats and Black Worldschoolers Mobile Bookstore, providing access to culturally relevant literature to inspire the youth of tomorrow. The Indianapolis area launch will take place March 6th 3 pm-6pm at KIPP Indy Legacy High School, and is powered by Cummins Inc.

We are inviting local and national media outlets to attend this groundbreaking event as well as to print details in order to raise awareness to the importance of having access to culturally relevant literature within our communities.

For additional information on the news that is the subject of this release (or for a sample, copy or demo), contact Dr. Russell J. Ledet at contact@the15whitecoats.org..

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Cummins Inc.

Cummins, a global power technology leader, is a corporation of complementary business segments that design, manufacture, distribute and service a broad portfolio of power solutions. The company’s products range from internal combustion, electric and hybrid integrated power solutions and components including filtration, aftertreatment, turbochargers, fuel systems, controls systems, air handling systems, automated transmissions, electric power generation systems, microgrid controls, batteries, electrolyzers and fuel cell products.

Cummins’ Statement on South Carolina’s Proposed Abortion Ban

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Over the past few months, Cummins has been communicating internally to our employees, and publicly, our concerns with laws and proposals that limit the ability of people to make decisions about their reproductive healthcare. We are very concerned with the proposed legislation in South Carolina that would limit reproductive healthcare access. 

If passed, this legislation will impact our employees, our communities and impede our ability to attract and retain a diverse workforce in South Carolina. Cummins believes that women should have the right to make reproductive healthcare decisions as a matter of gender equity, ensuring that women have the same opportunity as others to participate fully in the workforce and that our workforce is diverse. South Carolina’s proposed legislation is contrary to this goal.

For Cummins to be successful it is critical that we have a safe and welcoming workplace, and communities where we embrace our differences and enable all employees to thrive. As we continue to grow our footprint with a focus on selecting communities that align with our values and business goals, this law will be considered in our decision-making process.

We want to make it clear that Cummins will continue to provide our employees with access to high-quality, affordable healthcare, regardless of where they live and are able to make healthcare decisions based on what they believe is right for them.

Cummins Office Building

Cummins Inc.

Cummins, a global power technology leader, is a corporation of complementary business segments that design, manufacture, distribute and service a broad portfolio of power solutions. The company’s products range from internal combustion, electric and hybrid integrated power solutions and components including filtration, aftertreatment, turbochargers, fuel systems, controls systems, air handling systems, automated transmissions, electric power generation systems, microgrid controls, batteries, electrolyzers and fuel cell products.

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