What Are Spark Plugs?
Spark plugs produce the energy needed for an engine’s internal combustion process to occur. Find out more about how they work and the different kinds here.
- Programs
- Locations
- Explore UTI
- Training & Admissions
- Support & Financial Aid
- Current Students & Alumni
- Employers & Partners
Under the hood of a vehicle, the air intake system allows air to reach the engine – a key part of the combustion process.
Different parts make up this system, including the throttle body.
If your dream is to be an auto mechanic, you need to know how engines work. That includes understanding the critical functions of a throttle body through and through.
Continue reading to find out more about how the throttle body works and its importance to modern vehicles!
Key Summary Points
- The air intake system in a vehicle allows air to reach the engine, and the throttle body is a component of this system.
- The throttle body contains a throttle plate that opens and closes to control the airflow into the engine.
- The location of the throttle body depends on the vehicle's engine type, with older models having it built into the carburetor and newer models having it between the intake manifold and air filter.
- A throttle body spacer can be added to increase the amount of airflow into the engine, potentially improving horsepower and fuel economy.
- Signs of a failing throttle body include dirt buildup, poor idling, uneven acceleration, leaks and electrical problems. It is important to have these issues addressed by a trained technician.
What Does a Throttle Body Do?
Function of throttle body
Within the air intake system, a housing unit contains a throttle body component called the throttle plate, also known as a butterfly valve. This plate rotates on a shaft.
When a driver steps on the gas pedal, the throttle plate opens to allow air into the engine. When the pedal is released, the valve closes. This chokes — or throttles — the airflow in the combustion chamber, which helps control the speed of the engine.
Locations of the throttle body
The throttle body can be found in different areas, depending on a vehicle’s engine type.
1. Directly in the carburetor: mostly applies to older models, used for fuel injection.
2. Between the intake manifold and the air filter: In late-model fuel-injected engines, the throttle body is connected mechanically to the gas pedal via wire/cable.
Most engines feature electronic fuel injection. In this case, a throttle position sensor sends a signal to the electronic control unit (ECU) when the driver steps on the gas pedal. This prompts the airflow sensor to communicate with the computer as well, increasing the amount of fuel the injectors provide.
What does a throttle body spacer do?
A part that some car owners like to add to their throttle body system is a throttle body spacer — a small metal circle typically installed between the air intake and the throttle body itself. This part is used to change the amount of airflow going into the intake manifold.
Image credit: Summit Racing Equipment
A throttle body spacer maximizes the amount of airflow to the engine by allowing in more air than usual. The goal is to increase the engine’s horsepower and fuel economy.
This increase in airflow and velocity can make engine operation more efficient and prevent it from working so hard, which can result in better automotive performance.
Read: What Is a Catalytic Converter and What Does It Do?
Signs That a Throttle Body Is Wearing Out
Like any other part, throttle body system components can start to wear out and experience issues. It’s important to pay attention to possible warning signs and get problems taken care of as soon as possible.
Signs of a failing throttle body part include:
- Dirt and other buildup: The housing of the throttle body can start to accumulate dirt and other deposits, which can cause the air/fuel flow to become interrupted.
- Poor idling: A common sign that a throttle body is operating poorly or lower-than-normal is idling. This means the vehicle stalls when pressing the gas pedal rapidly or after coming to a stop.
- Uneven acceleration: Air and fuel gets released into the engine when you press on the gas pedal, but a worn throttle body could prevent the engine from getting the power it needs. If your car is taking longer to gather speed, it could be a throttle body issue.
- Leaks: The air/fuel flow can get disrupted from vacuum leaks, which can be caused by a throttle stop that’s wearing down or isn’t adjusted properly.
- Electrical problems: Connection problems with the throttle body sensor can cause communication issues with the ECU, which results in a drop in power.
Be sure to take your vehicle to a trained technician to determine the source of the problem and get things running properly again!
Throttle Body FAQs
1. Can you explain the purpose of a throttle body in a vehicle's engine?
The throttle body regulates the amount of air entering the engine, which is crucial for maintaining the proper air-fuel mixture needed for combustion. By controlling the airflow, it directly impacts the engine's power and speed.
2. What are the main components of a throttle body?
The primary throttle body parts include the throttle plate or butterfly valve, the housing unit and the throttle position sensor. These elements work together to manage airflow and communicate with the vehicle's ECU.
3. How does a throttle body control the airflow in an engine?
The throttle body controls airflow by adjusting the throttle plate. When the gas pedal is pressed, the throttle plate opens to allow more air into the engine. When the pedal is released, the plate closes, restricting airflow.
4. What are the symptoms of a faulty throttle body?
Symptoms of a faulty throttle body include poor idling, uneven acceleration and an accumulation of dirt in the throttle body's housing. In some cases, there may also be vacuum leaks or electrical problems affecting the throttle position sensor.
5. Can a dirty throttle body affect the performance of a car?
Yes, a dirty throttle body can affect a car's performance by interrupting the air/fuel flow, leading to issues like poor idling and decreased acceleration. Cleaning the throttle body can help restore normal function and improve overall engine performance.
Read: What Are Anti-Lock Braking Systems (ABS)?
Get Training With Air Intake Systems at UTI
Want to learn skills that can help you perform maintenance on vehicles and their parts, including the throttle body? The Automotive Technology program at Universal Technical Institute (UTI) features courses and hands-on training that cover the fundamentals of automotive maintenance and repair.18
Not only could this help you make repairs, but you could also apply this knowledge to a career in an in-demand industry.1 In fact, the Bureau of Labor Statistics projects more than 67,000 estimated average annual automotive technician job openings in the United States.41
Find out how you can get started by requesting more information through our website or by calling an Admissions Representative at 1-800-834-7308 today!
UTI Campuses That Offer Automotive Technician Training
YOU COULD START YOUR EXCITING NEW CAREER AS A MECHANIC OR TECHNICIAN TODAY.
With classes starting every 3-6 weeks, no need to wait to start your career.
Hands-on training.Get hands on experience with the industry's leading brands.
No Pressure to commit.Get answers to your questions without any obligations.
1 ) UTI is an educational institution and cannot guarantee employment or salary.
2 ) For program outcome information and other disclosures, visit www.uti.edu/disclosures.
18 ) UTI now offers all of its automotive, diesel, motorcycle and marine technician training in a blended-learning format consisting of online lecture courses along with in-person, hands-on lab training.
41 ) For Automotive Service Technicians and Mechanics, the U.S. Bureau of Labor Statistics projects an annual average of 67,800 job openings between 2023 and 2033. Job openings include openings due to net employment changes and net replacements. See Table 1.10 Occupational separations and openings, projected 2023-33 U.S. Bureau of Labor Statistics, www.bls.gov, viewed November 4, 2024. UTI is an educational institution and cannot guarantee employment or salary.
Universal Technical Institute of Illinois, Inc. is approved by the Division of Private Business and Vocational Schools of the Illinois Board of Higher Education.
TRAINING FOR A NEW CAREER STARTS HERE
Take 60 seconds and find out how you can get trained.