Your Car Jerks When Stopped at Light? Here is What To Do!

If you’ve ever been stopped at a red light in your car and felt it jerk, then you know how alarming the situation can be. Usually a faulty coil pack or dirty throttle body can cause a car jerks when stopped at light, but there could be other factors at play.

Fortunately, this issue is usually not serious, but that doesn’t mean it’s something you should ignore. Identifying the cause of the jerking is essential for keeping your car running smoothly and safely. Let’s take a look at these  potential causes in more detail.

2 Common Causes Make Your Car Jerks When Stopped at Light

2 Common Causes Make Your Car Jerks When Stopped at Light

Faulty Coil Pack 

If your car begins to jerk or shake when stopped at red lights, one possible cause could be a faulty coil pack. The coil pack is responsible for delivering power to the spark plugs which ignite the fuel in each cylinder of your engine.

Over time, these packs can wear out and lose their efficiency, resulting in misfires and rough idling which can lead to jerking when stopped at red lights. If this is the case with your vehicle, then replacing the coil pack should resolve the issue quickly. 

Replacing a coil pack can be costly, but it’s an essential step in ensuring the reliable operation of your vehicle. Depending on the make and model, replacing a coil pack could cost you anywhere from $130 to over $300.

It is important to understand that the actual repair work required for replacing the coil pack can be far more complex than anticipated so it may be wise to seek help from a qualified professional instead of trying to do it yourself.

Dirty Throttle Body 

Another common cause of jerking when stopping at red lights is a dirty throttle body. A throttle body is usually mounted between the air filter housing and the intake manifold of an internal combustion engine. 

This part of your engine helps control air flow through the engine by adjusting itself based on how much pressure is being applied to the accelerator pedal by the driver.

The throttle body consists of a butterfly valve connected by a rod or cable to either an accelerator pedal or lever. When you press down on the accelerator pedal, you open up this valve and more air is allowed into the engine.

Over time, dirt and debris can build up on this component, causing it to become clogged and preventing it from moving as freely as it should. When this happens, it can cause jerky movements when coming to a stop as well as poor acceleration performance when accelerating from a dead stop.

Cleaning or replacing your throttle body should resolve this issue once and for all. The cost can vary greatly depending on the make and model of your car, and whether you are having the issue resolved by a professional mechanic. Cleaning throttle body cost from $200 to $300 and replacing it can cost between $400 and $600.

Many mechanics will take apart the entire air intake section of your vehicle to avoid any future issues that may arise if they only cleaned the throttle body. That is why the cost may be higher in some cases – the process takes much longer due to other parts and components that need to be removed, inspected and eventually put back together. It’s important to evaluate all costs before starting this service in order to prevent any surprises.

These are two of the most common causes of a car jerking when stopped at light, but if it jerk when you are accelerating or driving at constant speed it could also be caused by other factors such as a bad spark plugs, vacuum leaks or dirty fuel injectors.

If you are unable to fix the problem on your own then it’s best to take your car to a qualified mechanic in order to have them diagnose the issue and recommend an appropriate solution.

Armed with this information, you can get your car back in top shape and enjoy a smooth, comfortable ride once again. Be sure to take care of the issue as soon as possible so that you can stay safe on the roads!

How Often Should You Clean Throttle Body?

How Often Should You Clean Throttle Body

The frequency with which you should clean your throttle body will depend on several factors such as driving habits, road conditions, type of vehicle, etc.

Generally speaking, it’s recommended that you clean your throttle body every 15-20 thousand miles or once a year if you are not sure how many miles are on your vehicle’s odometer.

It’s also a good idea to inspect your throttle body regularly in between service intervals, make sure there are no cracks or other signs of damage that could affect its performance.

Additionally, if you notice any strange sounds coming from your engine or poor acceleration while driving, these could be signs that something isn’t right with your throttle body and should be checked out as soon as possible.  

How Can I Clean My Throttle Body at Home?

How Can I Clean My Throttle Body at Home

Luckily, cleaning the throttle body is a relatively simple process that can be done at home with minimal tools and time. Let’s take a look at what you need to do in order to get your engine running more efficiently. 

What You’ll Need 

Before we get into the nitty-gritty of how to actually clean your throttle body, let’s first go over the supplies you will need for the job.

To properly clean the throttle body, you will need an air compressor or air gun, a set of nut drivers or wrenches (depending on what type of bolts secure your intake manifold), three cans of throttle body cleaner, and some rags or paper towels.

You may also want some gloves for extra protection if you are sensitive to chemicals. All of these items should be easy enough to find at any local auto parts store or online retailer. 

How To Clean Your Throttle Body 

Now that you have all of the supplies necessary, it’s time to get started on cleaning your throttle body!

  1. First, make sure that the engine has cooled off completely before beginning any work as hot engines can be dangerous and cause injury.
  2. Once it has cooled off enough, locate the air intake tube on your vehicle and remove it from its bracket with either nut drivers or wrenches (depending on what type of bolts are used).
  3. Once this is done, use an air compressor or air gun to blow out any debris that may have collected inside the tube.
  4. Next, spray some throttle body cleaner directly onto the inside walls of the tube and wipe away any dirt and grime with either a rag or paper towel.
  5. Finally, reattach the air intake tube back onto its bracket and start up your vehicle—you should immediately notice increased performance!   

Cleaning your throttle body is an easy way for car owners to improve their engine performance without having to take their vehicles into shops for expensive repairs or replacements.

With just a few simple steps and minimal supplies from your local auto parts store, you can keep your engine running smoothly for years down the road!


Your car jerking when stopped at light can be caused by several different issues such as faulty coil packs or dirty throttle bodies. Identifying what’s causing this behavior in your vehicle is important for keeping it running smoothly and efficiently so that you don’t experience any further problems down the road.

If you’re having trouble determining what’s causing your car to jerk while stopped at red lights, it may be best to take it into an automotive service shop where they can identify and diagnose any underlying problems more accurately than you could do yourself.

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James Todd

I'm James. I've been a car mechanic for as long as I can remember. It's always been my dream to work on cars, and I love it more than anything. I love the challenge of figuring out what's wrong with them and fixing them. I'm good at my work, and people often come to me for advice. I'm happy to help out whenever I can, and I always try to learn something new. I enjoy nothing more than helping people keep their vehicles running smoothly - it's what makes me happy.

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