It can be frustrating and even a little scary when your car jerks while accelerating at low speeds.
Therefore, understanding why this happens and how to fix it can help you keep your car running smoothly and safely.
Common Causes of Car Jerking
Dirty Fuel Injectors
In the engine, fuel injectors spray fuel into the combustion chamber. However, they can get dirty or clogged due to impurities in the fuel.
When this happens, the fuel injectors cannot deliver the correct amount of fuel, leading to an uneven fuel-air mixture. The imbalance can cause the engine to misfire, resulting in a jerking motion when you try to accelerate.
To fix this issue, you can use a fuel injector cleaner, which is an additive that you pour into your gas tank. This cleaner helps dissolve the deposits inside the injectors.
Worn Out Spark Plugs
However, spark plugs can wear out or become fouled with carbon deposits. When spark plugs are not functioning correctly, they can cause the engine to misfire, leading to jerking during acceleration.
Replacing spark plugs is a relatively simple and inexpensive fix.
Dirty Air Filters
Air filters are responsible for keeping dirt, dust, and debris out of the engine. When air filters are clogged or dirty, they restrict airflow into the engine. Then it can cause an improper fuel-air mixture, making the engine run poorly and jerk during acceleration.
Cleaning or replacing air filters is an easy and cost-effective solution. Most car manufacturers recommend changing the air filter every 12,000 to 15,000 miles.
Blocked Catalytic Converters
The catalytic converter is an important component of your car’s exhaust system.
A blocked catalytic converter can restrict exhaust flow, causing the engine to lose power and jerk during acceleration. Using a catalytic converter cleaner can help remove deposits and improve performance.
Damaged Gas Lines
Gas lines transport fuel from the tank to the engine. If these lines become damaged or develop leaks, the engine may not receive a consistent supply of fuel, resulting in jerking or hesitation during acceleration.
You can inspect gas lines for visible damage or leaks.
Defective Carburetors
Carburetors are responsible for mixing air and fuel before it enters the engine. If the carburetor isn’t working properly, it can create an improper fuel-air mixture, causing the engine to run poorly and hesitate during acceleration.
You can clean, repair or replace the carburetor to resolve this issue.
Moisture on the Distributor Cap
In cold or damp weather, moisture can collect on the distributor cap. The distributor cap is part of the ignition system, and moisture can make the engine misfire, which leads to hesitation during acceleration.
To prevent this issue, keep your car in a garage or use a thermal cover during cold weather.
Diagnose the Problem
Listen and Feel
Paying close attention to your car’s behavior can provide valuable clues about the cause of jerking. Notice when and how the car jerks.
Does it happen only at low speeds, or does it occur at higher speeds as well? Is the jerking more pronounced when the engine is cold, or does it happen regardless of the engine temperature? These details can help you narrow down the potential causes.
For example, if the car jerks only when accelerating from a complete stop, it might indicate an issue with the fuel delivery system. If the jerking occurs at various speeds, it could point to a problem with the ignition system or air intake.
Check for Warning Lights
Modern cars are equipped with onboard diagnostic systems that can detect many issues. If a warning light appears on your dashboard, it can provide valuable information about the problem.
Common warning lights related to engine performance include the Check Engine Light, which can indicate issues with the fuel system, ignition system, or emissions control.
Using an OBD-II scanner, you can read the diagnostic trouble codes (DTCs) stored in the car’s computer. These codes can help pinpoint the specific problem and guide you in finding the appropriate solution.
Inspect Key Components
Visually inspecting key components of your car’s engine can help identify potential issues. Start by checking the spark plugs, fuel injectors, air filters, and other critical parts. Look for signs of wear, damage, or dirt buildup.
For example, if the spark plugs appear fouled with carbon deposits, they may need to be replaced. If the air filter is clogged with dirt and debris, it should be cleaned or replaced. Inspecting these components regularly can help you catch problems early and prevent more significant issues down the road.
Fix the Problem
Clean or Replace Parts
Many causes of car jerking can be resolved by cleaning or replacing specific parts. For instance, if dirty fuel injectors are causing the problem, using a fuel injector cleaner can help dissolve deposits and improve performance. Similarly, replacing worn-out spark plugs can restore proper ignition and prevent misfires.
Cleaning or replacing air filters is another straightforward fix. A clean air filter ensures that the engine receives the right amount of air, leading to a proper fuel-air mixture and smooth acceleration.
Use Additives
Fuel and catalytic converter cleaners are additives that can help remove deposits and blockages in the fuel system and exhaust system. These cleaners are easy to use—simply pour them into the gas tank according to the instructions on the product label.
Using these additives regularly can help maintain the cleanliness of the fuel injectors, carburetor, and catalytic converter. This can improve engine performance and prevent jerking during acceleration.
Visit a Mechanic
If you’re not comfortable diagnosing or fixing the problem yourself, it’s best to visit a mechanic. A professional mechanic has the tools and expertise to identify and fix the issue quickly.
They can perform a thorough inspection of the engine, fuel system, ignition system, and other components to determine the root cause of the jerking.
In some cases, the problem may be more complex and require specialized equipment or knowledge to fix. A mechanic can provide a detailed diagnosis and recommend the appropriate repairs to ensure your car runs smoothly.
Prevent Future Problems
Regular Maintenance
Regular maintenance is key to preventing car jerking and other performance issues. Following the manufacturer’s maintenance schedule can help keep your car in optimal condition. It includes regular oil changes, air filter replacements, spark plug checks, and other routine services.
By staying on top of maintenance tasks, you can catch potential problems early and address them before they become more significant issues. Regular maintenance also helps extend the lifespan of your car and ensures it runs efficiently.
Use Quality Fuel
Using high-quality fuel can make a significant difference in your car’s performance. High-quality fuel contains fewer impurities and additives that can clog fuel injectors and other components.
Avoiding cheap, low-quality fuel can save you money in the long run by preventing clogs and deposits that can lead to jerking and other issues.
Consider using fuel additives designed to clean the fuel system and improve performance. These additives can help keep the fuel injectors, carburetor, and other components clean and functioning correctly.
Drive Smoothly
Your driving habits can also impact your car’s performance. Avoiding hard acceleration and braking can reduce wear and tear on the engine and other components. Smooth driving helps maintain a consistent fuel-air mixture and prevents unnecessary stress on the engine.