Having the right quantity of air in the engine is essential for internal combustion to take place and optimal performance of your engine. It is the role of the throttle body to regulate the amount of air that enters the combustion unit, such that there is a balance between the air and fuel level, for proper combustion to occur.
The throttle body is designed to regulate airflow to the engine in fuel-injected vehicles. For your engine to perform optimally, an adequate amount of air must be present in the combustion chamber, and this is made possible by having a functional throttle body in your vehicle.
The throttle body is an essential component of the engine that cannot be bypassed. Over time, the throttle body can wear out or get dirty and will affect the operation of the engine. Problems with this component can cause several issues to your vehicle which will be discussed in this article.
What is a Throttle Body?
The throttle body is an engine component that controls the amount of air that makes its way to the internal combustion chamber, by opening up the throttle plate or adjusting the plate’s positions to ensure the right amount of air is entering the engine at a particular time.
The component is located between the engine and the intake manifold, and it helps the fuel injectors determine the quantity of fuel to release, based on the amount of air coming into the engine.
This component ensures the engine is not too air-fuel rich or too lean by opening and closing the throttle plate once the accelerator pedal is depressed.
The major component of the throttle body is the throttle plate because the position of the plate in the throttle body determines airflow to the engine. The throttle plate is connected directly to the gas pedal and when a user presses on the pedal, the plate rotates, allowing air to pass through.
What Causes Throttle Body Issues?
Several factors lead to throttle body issues. The most common is a dirty throttle body. Since this component is in the engine, it is prone to debris and carbon deposits which will build up and obstruct the free flow of air. Dirt, grime, and gunk that buildup on the throttle body clogs the throttle plate and other parts of the throttle body, thereby affecting its performance.
Other causes of throttle body issues include:
- Problems with the throttle position sensor: When the TPS is faulty, the valve will be stuck open or closed and the activities of the throttle body will be affected.
- Vacuum leaks: Vacuum leaks can be triggered by broken hoses, tubes, gaskets, or a loose clamp. When there is a vacuum leak, unwanted air, more than what is allowed by the throttle body, gets into the combustion chamber, and will cause problems.
- Electrical problems: This is quite rare, but it occurs. It is common in older cars because these electrical connections have been subjected to prolonged heat emanating from the engine. Electrical connections can also be damaged due to physical contact during a past repair process.
- Failure of a part of the throttle body: If a component like a butterfly valve fails due to age, wear out or physical contact, it will cause problems to the throttle body.
- Faulty gas pedal: if the accelerator pedal is bad, it might be disguised as a throttle body issue because both components display similar symptoms when faulty.
What are the Symptoms of a Bad Throttle Body?
Problems with the throttle body will affect the performance of your vehicle and will make driving difficult. A faulty throttle body will exhibit several symptoms.
A faulty throttle body can cause your car to stall frequently. This stalling can occur while idling or when you try to start the car.
A bad throttle body could be one reason your car is producing and releasing more emissions.
When the throttle body is faulty, the valve can be stuck open, allowing excessive air into the engine. Excessive air in the engine will cause the fuel injectors to release more fuel to balance up the air-fuel ratio. This will make the engine run rich and will in turn increase the emission rate.
A faulty throttle body will affect acceleration because the mixture of air and fuel in the engine is not balanced. This can be quite frustrating and makes driving very stressful.
A damaged or even dirty throttle body will cause your engine to rough idle. Your engine will vibrate frequently when this happens.
Poor engine performance
Combustion is a process whereby fuel and air are burnt in the internal combustion chamber to release energy for the functioning of the engine.
If the throttle body is faulty, it will fail to release an adequate quantity of air. This will affect the combustion and the performance of the engine.
Check engine light illuminates
Problems with engine components will trigger the check engine light on your dashboard. If the throttle body is dirty or damaged and begins to malfunction, the check engine light will come on.
When the problem is severe, the check engine stays on for a long time and will require you to have the throttle body checked urgently.
Changes in fuel consumption
A faulty throttle body will affect the engine’s fuel consumption. The engine might be needing too much or too little fuel, and this is determined by the quantity of air the throttle body releases.
A bad throttle body might lead to refueling frequently or less frequently. Refueling less frequently might look good to you but this is bad for your engine.
An imbalance in the air-fuel ratio due to a faulty throttle body will cause the engine to misfire. This symptom does not come in the early stages of the damage until it has been ignored for a long time.
How to Fix or Replace the Throttle Body
If you notice any of the symptoms discussed earlier, you might either need to fix or replace the throttle body.
Here are the procedures to repair or replace the throttle body.
- Inspect the air filter to know if it needs to be cleaned or replaced. The air filter is usually clogged with dirt, debris or other forms of contaminants and could be the reason your throttle body is failing.
- After cleaning or replacing the air filter, clean the throttle using a throttle body cleaner.
- You can clean the component by spraying the cleaner on it, leaving it for some minutes then wipe off with a rag.
- Reset the engine’s idle by turning the vehicle off and on intermittently.
- While resetting the idle, press on the gas pedal for some seconds and release it. If the throttle body still does not work while doing this, it will need a replacement.
Replacing the Throttle Body
- To replace the throttle body, you will need tools like, a socket set, screwdrivers, a flashlight, and a new throttle body. This process is quite easy but will take a little time.
- The first thing to do is to disconnect the negative terminal from the battery before you commence work to prevent electrocution.
- The throttle body is usually between the engine and intake manifold, so take off the intake hoses to easily access the component.
- Using the socket set and screwdrivers, take off bolts and pull out the old throttle body.
- Install the new throttle body. It should be OEM specifications, carefully screw in the bolts to fit it in.
- Reconnect the negative terminal on the battery and test drive your car.
Cost of replacing the Throttle Body
The cost of replacing the throttle body varies based on the model and make of your vehicle. The component is a bit expensive, which is why it is important to clean the component first before thinking of a replacement.
Most throttle body problems come from a dirty throttle body, and you might be wasting your money to replace the component when it only needs to be cleaned. Replacing this component costs between $450 to $600. The part is more expensive than labor and will cost between $400 to $500 while labor costs just $50 to $150.
Frequently Asked Questions
Where is the Throttle Body located?
The throttle body is directly connected to your accelerator pedal, and it is mounted in an area between the air intake manifold and the engine. It is found in the engine compartment of your vehicle.
Is it safe to drive with a bad Throttle Body?
No! It is not safe to drive with a bad throttle body. The throttle body makes the flow of air to the engine possible, and air is required for combustion. If this process is hindered, the engine will stall, rough idle, misfire and even fail to accelerate. This can make driving stressful and hazardous.
How long will the Throttle Body last?
As a mechanical component of a car, the throttle body can last for up to 150,000 to 200,000 miles if properly handled. Cleaning the throttle body at least once every 75,000 miles will enhance its longevity.
Do I need to clean or replace my Throttle Body?
Cleaning or replacing the throttle body depends on the severity of the problem. Sometimes, it might just be debris or other forms of contaminants clogging the air filter or other parts of the throttle body that are causing the problems. At this point, all you need to do is clean the component with a throttle body cleaner. Other times, the component can be severely damaged which will require a replacement.
Will a bad Throttle Body throw a Code?
Yes! A bad throttle body will cause the check engine light to illuminate and will throw error codes on the dashboard. When this happens, it is vital to have the throttle body inspected and fixed.
Can I replace the Throttle Body at Home?
Yes! This is very possible. In most car models the process is quite straightforward. All you need is some basic knowledge of car servicing and the required tools. You can consult the service manual for little tips.
How can I reset the Throttle Body?
Resetting the throttle body might vary depending on your car model or make. For some models, what is required is disconnecting the battery for a short period and the throttle body will automatically reset. For some other car models, you will need a diagnostic tool. Consult your service manual to know what method is peculiar to your car.