There are a few different reasons why your car might be suddenly jerking when you press the gas. We rounded up the symptoms and possible causes so that you have everything you need to know in one place, making it easier to fix.
If you find yourself asking, “Why is my car with automatic transmission jerking when accelerating?” we have the answers. These are the possible symptoms of why your car might jerk suddenly.
1. The Catalytic Converter is Blocked
This part is where the pollutants are filtered through before they leave your car’s exhaust pipe. When it is blocked, too much air can get mixed into your car’s fuel- leading to issues in the exhaust system.
Over time, this will cause a delay when you press on the gas. You will notice your car jerks when driving on the highway before you notice it in your daily driving routine.
Additional symptoms of blockage would include your car’s fuel efficiency dropping, the check engine light appearing, and the smell of hydrogen sulfide- which smells strongly of rotten eggs.
You can try to clear small blockages yourself with a commercial catalytic converter cleaner. If you still have problems with jerking and stuttering, take the car to an auto shop for the repair.
Related: Is It A Good Idea Driving With A Bad Catalytic Converter?
2. The Fuel Injectors are Dirty
Dirty fuel injectors can cause several problems. They can cause your car to jerk when slowing down, lose power entirely, or make it jerk when at a consistent speed. This is a common problem that can be very annoying.
You will be able to hear the problem easily, as your car’s engine will be frequently stuttering and making a lot of noise.
If you take the time to clean the fuel injectors often, you will be able to avoid this problem. You can do this easily by using a special cleaner unless they are too dirty.
In those cases, it is best yo remove the injectors and clean them by hand- or even replace them in the worst-case scenario.
3. The Air Filter is Dirty
If your car jerks when accelerating uphill, this may be the culprit. When there is too much air mixed into your car’s fuel, problems arise- more often than not leading to a jerking car. However, too little air also can cause issues.
When the air filter is dirty, it allows dirt and debris to make their way into your engine. This leads to jerking and can cause more issues the longer you let it sit.
The air filter is easy to replace and is relatively cheap. So, if it is filthy, you are going to want to get a new one. This will improve the health and longevity of your car’s engine, as well as stopping it from jerking.
Related: When Should You Replace The Engine Air Filter?
4. The Fuel Pump is Failing
A jerking car usually stems from issues with the fuel supply, meaning the fuel pump failure is another common cause. If your car jerks when stopped, this could be why.
The fuel pump determines how much fuel is being sent to the engine. When it is not getting enough, this causes the car to jerk forward when the engine tries to take more fuel than it is currently receiving.
You will want to have your car checked at an auto repair shop if this is the case.
5. The Spark Plugs are Bad or Dirty
This is one of the easiest to determine symptoms of why your car is behaving strangely. If you notice that your car jerks when accelerating uphill, this would likely be the reason why.
A dirty or faulty spark plug keeps the fuel from igniting properly in the cylinder, causing stuttering when you push on the gas.
This is one of the easiest symptoms to fix as well- all you need to do is replace the spark plugs that are giving you trouble.
It is a good idea to keep all of them replaced if you have forgotten the last time you changed them. This ensures that they all are in working and order and will last around the same amount of time. It is a cheap and quick fix too.
6. The Accelerator Cable is Wearing Out
In some cars, there is still an accelerator cable connecting the throttle to the gas pedal. It is not uncommon for this connecting cable to wear out in older cars.
When this happens, it causes the car to react slower to you stepping on the gas- then suddenly accelerating.
This symptom is easy to identify, as the damage to the cable is usually noticeable by the time it starts causing you problems.
You will want to take it to a repair shop right away because the car will quit working as soon as the accelerator cable snaps.
7. Condensation in Winter
If you notice your car starts jerking in winter and you have not had a problem with it before, then it is likely condensation underneath of the distributor cap.
The water will evaporate as the engine heats up, meaning it can just take your car a bit of time to “thaw” when you start it in the cold.
However, if this problem continues happening, the engine is going to start struggling more and more in the cold.
You can prevent this from happening by putting a thermal cover on the cap to protect it from condensation or park your car in a garage if you can.
So, if you are often asking yourself, “Why is my car with automatic transmission jerking when accelerating?” then one of those seven common reasons could be causing the problem.
Stuttering is not uncommon in many cars and can be easy to fix. If you are having trouble identifying the source of the sudden jerking, then a mechanic will be able to help you.
Some of these problems are more serious than others, so getting your car fixed right away can help save your engine.