Home Diagnosis and TroubleshootingEngine Problems Bad Throttle Body Symptoms – All The Different Symptoms

Bad Throttle Body Symptoms – All The Different Symptoms

by Jordan Harris
Bad Throttle Body Symptoms

Are you experiencing some weird symptoms in your car like a check engine light and rough idle from the engine? In this case, you might be experiencing some bad throttle body symptoms. But you shouldn’t worry because we are going to help you out to diagnose this problem in the right manner.

Having a problem like this can be extremely difficult to deal with. This is the case because the throttle body is an integral component that keeps your engine alive. Without a throttle body, the engine will simply stop working and you will not be able to run your car.

When a throttle body is closed is quite similar to when you close your nose with your hand. You can’t breathe. And so is the case with the internal combustion engine. When the butterfly flap is closed, the engine will shut down. So, you understand the importance of it when it comes to keeping the engine running. But when the throttle body fails, there could be a number of different symptoms. And we are going to help you out understand them.

First, we are going to learn what is a throttle body and how does it work. Then we will learn the bad throttle body symptoms and then we will learn how to diagnose the problem. After we will discuss sorting this problem out and the costs involved. So, if you want to learn more, follow along.

What Is A Throttle Body?

So, before we dive into more complex topics such as the bad throttle body symptoms. Let’s first learn what is a throttle body in general. This will be extra useful for beginners who are not into cars and want to get a basic grasp of the problem and learn more about this component. So, if you are one of them, follow along, if not, you can jump right to the bad throttle body symptoms.

Nevertheless, a throttle body is a component that every internal combustion has. But what is a throttle body?

In simple terms, a throttle body is only a butterfly flap that opens and closes when there is a need to do so. But why does it open and close? Well, it does this in order for the air to get inside of the engine intake and the combustion process to be complete.

If the throttle body is closed, there will be no combustion because no air will get inside and maintain this combustion.

The throttle body is basically a butterfly flap that is installed into a housing. On the side of the housing, there is the throttle body position sensor that reads the position of the throttle body flap and tells the engine how much air and fuel to dump into the engine. Simple as that.

There is no complexion in this component. Its work is really straightforward. But we cannot say that about the throttle body symptoms, which can be many. But more on that later. Let’s first learn why the throttle body is so important in detail.

Why The Throttle Body Is So Important?

Before we dive into the topic of the bad throttle symptoms. Let’s further elaborate on this component and learn more about its function. Why it is so important and why it is essential in the work for the engine? Let’s discuss.

This throttle body is basically the component that directs how much air there will be into the engine combustion process. The location of the throttle body is between the mass airflow sensor and the air intake of the car. A car can have one or two throttle bodies. One throttle body per bank.

Meaning that if you run a V6 or V8, you will have two of them. If you have a straight-4 or straight-6, then only one throttle body.

As we discussed above on the throttle body there is a flap that is opened and closed by a steel wire. Whenever you press on the gas pedal, you are basically pulling the wire and the flap opens. When you depress the gas pedal, the flap returns to its idle position. Allowing enough air to get inside of the engine so the engine could idle normally.

Also, something that we mentioned in the previous chapter is the throttle body position sensor. This sensor is usually mounted on the side of the throttle body. This sensor directly communicates with the engine computer also known as ECU.

This data is shared with the ECU and then based on the position of this throttle body. The ECU decides how to adjust the air to fuel mixture in the right manner. So, you can understand the cruciality of the throttle body. Without being in proper health, you will face some bad throttle body symptoms. More on that in a bit.

How Long Does A Throttle Body Last?

Now before we dive into the bad throttle body symptoms. Let’s see how long does a throttle body last. Meaning how much life you can squeeze from a throttle body before it fails?

And the short answer to this question is that throttle bodies rarely break down completely. Usually, these components last about 150,000+ miles.

What is bad though is that these throttle bodies require cleaning. So, whenever you think that the throttle body is bad, you probably have a problem with a dirty throttle body (which you can figure out how to clean a throttle body). Yep, that’s right.

The throttle body gets extremely dirty and a lot of these problems happen because some gases are returned into the intake and these gases are basically sticking to the intake and the throttle body. So, what happens is that the throttle body flap gets clogged with this sticky and grimy mess. Also, the dirt that gets sucked in from the intake starts to stick to the throttle body and this creates a mess.

You get annoyed by bad throttle body symptoms and the only solution would be to address the problem. But what are these bad throttle body symptoms? Let’s elaborate on them in the following chapters in-depth.

Bad Throttle Body Symptoms

As we covered the basics and learned how the throttle body works in real life. Now we can move on with our quest in solving the problem by understanding the bad throttle body symptoms.

As we learned, this throttle body often becomes dirty and the flap isn’t working as it should. So, considering this there are a number of symptoms that could arise from this strange work of the butterfly flap. Some of them are concealed, while some of them are really obvious. In the following chapters, we will cover them in detail where we will learn more about them.

Later on, based on the bad throttle body symptoms, we will learn how to address and diagnose the problem. So, if you want to learn more, follow along.

1. Check Engine Light

The first in our list of bad throttle body symptoms is the check engine light. This light is unavoidable when the throttle body is broken or clogged. Whenever this happens, the ECU will get a ton of bad readings from a number of sensors. Mainly the throttle body position sensor as well as the MAF or MAP sensors.

This will cause the computer to show the check engine light and annoy you. But you shouldn’t look at this as an annoyance rather as a warning.

Bad Throttle Body Symptoms

Whenever the check engine light appears on the dash it is worth taking things further and deeper diagnose the issue. For this, you will need an OBD2 scanner to scan the car for codes. And if you get some error messages concerning the intake and the sensors that we mentioned above. You know where to look for the problem.

If for some reason the check engine light doesn’t turn on, you will need to rely on some other bad throttle body symptoms that we are going to discuss in the following chapters. So, keep up with us.

2. Engine Misfires

The second in our list of bad throttle body symptoms that we would want to discuss is the situation when you have frequent misfires.

Whenever there is a problem with the flap, there will be unmetered air that enters into the combustion and this could affect the work of the cylinders.

The explosions that would happen inside of the cylinders will be uneven because there is too much air and so little fuel. Resulting in poor engine performance and misfires.

You will be able to hear these misfires, they will sound like small ticks that come from the top of the engine. And in this case, if the butterfly flap isn’t working right, there will be misfires on all of the cylinders. Not only on one of them.

At the rear of the car, you will be able to hear the exhaust how it makes pops and bangs. Overall, not an ideal situation. But it means that you need to put your sleeves up and try to diagnose the problem as soon as possible if you don’t want to continue driving a car like this. And frankly, driving a car with bad throttle body symptoms is not something pleasant. More on that in the following chapters where we will elaborate on the other bad throttle body symptoms.

3. Rough Idle

The third in our list of bad throttle body symptoms is the rough idle of the engine. When the throttle body is broken it means that the flap is stuck or it moves from open to close all the time.

So, whenever there is motion in the butterfly flap, you will notice how the engine running at idle speeds will be uneven.

In situations when this throttle body is open, the revs can jump up to 2000 RPM or more at idle. Which is completely not normal. These are extreme situations though.

But it doesn’t mean that it could not happen to you. That’s why you need to be aware of this. In most situations, the needle of the tachometer jumps to 1200 RPM or the work of the needle varies all the time if the flap has play in it.

Either way, whenever you notice something like this, it is important for you to act quickly and try to sort things out. Don’t let the problem get worse and pay a ton more money in the process. Now let’s move to the next bad throttle body symptoms.

4. Stalling Problems

Now let’s move to the next symptom in our list of bad throttle body symptoms, which is the stalling issue. Yes, that’s right, the engine will love to stall if the butterfly flap on the throttle body is not working well.

If the throttle body stays closed and doesn’t want to open when you apply on the throttle will mean that the engine will not receive enough air in the intake. So, the combustion process would be incomplete.

5. Bad Air To Fuel Mixture

Another in our list of bad throttle body symptoms is the bad fuel to air mixture. This symptom is somewhat specific because it is not that easily distinguishable and is greatly connected to other symptoms like misfires, spark plug fouling, rough idle, and increased fuel economy.

What happens though, is that the engine in your car works on the wrong map. Meaning that the computer is really confused and cannot adjust the fuel to air mixture accordingly because the butterfly flap of the throttle body or the throttle body position sensor is broken.

The engine could run either lean or rich. When the engine runs lean, there is too much air and little fuel in the cylinder. When the engine runs rich, there is little air and too much fuel in the cylinder.

Both of these situations are really bad and indicate a problem. When the engine runs lean, you will notice a power loss and the engine would love to stall. When the engine runs rich, you will experience a strong gasoline odor from the exhaust along with the blue or black smoke from the unburnt fuel.

Both of these situations can hurt your car in a number of ways. That’s why it is of utmost cruciality for you to address them accordingly by sorting out the problem with the throttle body.

What is most important for you is to know the bad throttle body symptoms and try to diagnose the issue. But more on that a bit later after we cover the rest of the bad throttle body symptoms.

6. Poor Fuel Economy

We cannot talk discussing bad throttle body symptoms and not address the poor fuel economy.

As we mentioned above when we covered the bad fuel to air mixture, having a problem with the throttle body will also going to affect your fuel economy.

The fuel economy will worsen by quite a bit. Especially if the engine is running rich on fuel. The ECU will dump fuel inside of the cylinders trying to adjust the engine work and will make things even worse.

Bad Throttle Body Symptoms

Resulting in decreased fuel economy. You can expect the fuel economy to worsen by quite a big margin. If you notice that you are visiting the gas station more regularly than you used to, this is a clear sign that you have a problem with some sensor or with the throttle body itself. So, beware of these bad throttle body symptoms. They can be really annoying and very difficult to read and tackle.

Other components that can be greatly affected and produce bad throttle body symptoms might be the spark plugs, O2 sensor as well as catalytic converter. Whenever there is a problem like this with the throttle body, you should aware of these components and try to sort the problem out. But how you can diagnose a bad throttle body based on the bad throttle body symptoms? Let’s elaborate in the following chapters.

How To Diagnose & Fix A Bad Throttle Body?

Now as we covered the bad throttle body symptoms, let’s learn how to diagnose the issue on your car. So, how can you do that? Well, it’s very simple.

The first thing you will need to do is to locate the throttle body. Check where is the big airbox for the air filter and follow the intake hose until the point where it meets the intake manifold.

Loosen up the clamp that is holding the hose and remove it. Inspect the condition of the flap and see how it opens and closes. On the front side, it should look clean but usually, the buildup of debris is on the back. So, this will require the removal of the throttle body from the engine. Untighten the bolts and remove the throttle body.

Place the throttle body on a bench or another place where you could work on it. In order to fix it, you will only need to get some brake cleaner or a carburetor cleaner.

Carb cleaner would work better. It will easily remove the debris buildup that is on the flap as well as the debris on the housing.

Spray the throttle body and let it soak. Then get a toothbrush until you remove everything that has accumulated on the throttle body. When I mean everything I mean everything. Try to return the flap in OEM condition. Take your time and give it a good clean.

Then wipe it off and you can mount the throttle body on the engine. Start the car and see how it works. If it works well, then you solved the problem. If not, you will have to replace this component, unfortunately. This is essential if you don’t want more bad throttle body symptoms.

Cost To Fix A Bad Throttle Body

So, what is the cost to fix the bad throttle body and get rid of the throttle body symptoms? Well, that greatly depends much on the level of dirt that is there. Not every throttle body is cleanable. So, you can expect to replace the whole unit in some cases that are more extreme.

But in simple cases where the buildup is cleanable, you will be able to clean it for $10. Just grab a can of carburetor cleaner and take your time. Clean the component on a bench. If the dirt is too much, you will have to replace the whole unit. But how much does a throttle body costs?

Well, it is not as expensive as you think. It usually costs between $150 and $250. Depending much on the make and model. The labor of installing will also cost you between $50 and $150 depending on where you take your car to.

Overall, a good investment if you don’t want to deal with bad throttle body symptoms. With this throttle body, you can expect that your car will work like a charm.

If the problem persists, you might be needing to address other components. Namely, the throttle body position sensor. If similar problems still persist after cleaning the throttle body. Then you probably have a faulty throttle body sensor that is causing this problem with bad throttle body symptoms to happen.

Can I Keep Driving With Bad Throttle Body Symptoms

So, can you keep driving with bad throttle body symptoms? The answer to that question greatly depends on the extent of the buildup that is on the throttle body.

Bad Throttle Body Symptoms

In milder buildup driving the car will be possible but the more the buildup, the worse the driving experience will be. So, it is useful for you to clean the throttle body sooner and not allow the extent of the buildup to become too large and more damage to be done to the throttle body.

Conclusion To Bad Throttle Body Symptoms

In this article, we have covered quite a bit when it comes to the bad throttle body symptoms. First, we learned what is the throttle body and why it is really important. As we concluded the throttle body is the flap that opens and closes to allow air to get into the engine. Without it, you will face a ton of bad throttle body symptoms that we covered later on.

The most notable symptoms are the rough engine idle, poor fuel economy, check engine light, and overall poor performance of the vehicle.

Lastly, we learned how you can diagnose the problem and also fix the problem using carb cleaner. The solution for this problem most often is about $10. So, make sure that you sort it out quickly.

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