Common Causes of Car Jerking When Accelerating

Serving Shawnee, Overland Park & Greater Kansas City Area

Your car is jerking forward likely due to fuel system, ignition, transmission or air intake issues.

This mechanical issue can be alarming and leave you wondering about how extensive the repairs required will be. 

If you want to let a team of expert technicians take care of it, call Car City Wholesale's service department atl (913) 340-8020.

But a car jerking forward can be a common issue that many drivers face. 

In this article, we will go down a list of various causes of your car jerking during acceleration, how to diagnose the issue, and the solutions to fix and prevent it.

Common Causes of Car Jerking When Accelerating

1. Fuel System Issues

Dirty Fuel Injectors: Fuel injectors deliver fuel to your car's engine. Over time, they can become clogged with dirt and debris, leading to uneven fuel distribution. This can cause your engine to misfire and your car to jerk during acceleration. Regularly cleaning or replacing fuel injectors can help maintain smooth acceleration.

Fuel Pump Problems: The fuel pump delivers fuel from the tank to the engine. A failing fuel pump may not provide a consistent fuel supply, leading to jerking motions as the engine struggles to get enough fuel. Signs of a failing fuel pump include sputtering at high speeds, a decrease in fuel efficiency, and difficulty starting the car.

Fuel Filter Blockage: The fuel filter's job is to keep dirt and debris out of the fuel system. A clogged fuel filter can restrict fuel flow to the engine, causing it to run lean (not enough fuel) and resulting in jerky acceleration. Regularly replacing the fuel filter as part of your vehicle's maintenance schedule can prevent this issue.

2. Ignition System Problems

Worn Spark Plugs: Spark plugs ignite the air-fuel mixture in the engine's cylinders. Over time, they can become worn or fouled, leading to misfires and engine hesitation due to an absent or weak spark. 

Replacing spark plugs according to your vehicle's maintenance schedule can ensure smooth and efficient combustion. If you can't remember the last time you replaced your spark plugs and have owned your vehicle for years, this is a good place to start.

Faulty Ignition Coils: Ignition coils convert the battery's low voltage into the high voltage needed to create a spark at the spark plugs. A failing ignition coil can result in weak or inconsistent sparks, causing the engine to misfire and jerk during acceleration. If you notice rough idling, poor fuel economy, or difficulty starting your car, it might be time to check the ignition coils.

Distributor Cap Issues: In older vehicles, the distributor cap directs high-voltage electricity from the ignition coil to the spark plugs. Cracks or corrosion on the distributor cap can cause misfires and inconsistent engine performance.

3. Transmission Troubles

Transmission Fluid Levels: Low or dirty transmission fluid can cause the transmission to slip or hesitate, leading to jerky acceleration. Using the wrong type of transmission fluid can exacerbate the problem.

Worn Clutch (Manual Transmission): In manual transmission vehicles, a worn clutch can cause the car to jerk during acceleration. Signs of a slipping or worn-out clutch include difficulty shifting gears, a burning smell, and a spongy clutch pedal.

Automatic Transmission Issues: Automatic transmissions can develop issues such as slipping, delayed shifting, or harsh gear changes, all of which can cause jerking during acceleration. Regularly servicing the transmission and addressing any issues promptly can avoid any jerkiness.

4. Air Intake System Problems

Dirty Air Filter: The air filter prevents dust, dirt, and debris from entering the engine. A clogged air filter can restrict airflow, causing the engine to run rich (too much fuel) and resulting in jerky acceleration. This one is easy to check and doesn't really need you to go to a mechanic. Just open up the air filter in the engine bay and change it if it looks dirty. Should take you 5 minutes.

Mass Air Flow Sensor Malfunction: The mass air flow (MAF) sensor measures the amount of air entering the engine and helps determine the correct fuel-to-air ratio. A malfunctioning MAF sensor can send incorrect data to the engine control unit (ECU), causing the engine to run poorly and jerk during acceleration. Cleaning or replacing the MAF sensor can fix this.

Throttle Body Issues: The throttle body regulates the amount of air entering the engine based on the driver's input. Carbon buildup or other objects in the throttle body can cause it to stick or malfunction, leading to wonky acceleration. Cleaning the throttle body with a spray or deep clean can improve airflow and restore performance.

5. Engine and Emission System Problems

Vacuum Leaks: Vacuum leaks happen when there is an unintended gap in the engine's vacuum system, which can mess up the air-fuel mixture and cause the engine to run unevenly. Common signs of a vacuum leak include a hissing sound, rough idling, and jerky acceleration.

EGR Valve Issues: The exhaust gas recirculation (EGR) valve helps reduce emissions by recirculating a portion of the exhaust gasses back into the engine. A malfunctioning EGR valve can cause rough idling, poor acceleration, and increased emissions.

Catalytic Converter Problems: The catalytic converter reduces harmful emissions by converting exhaust into less harmful exhaust. A failing catalytic converter can cause a loss of power, poor acceleration, and jerky driving. 

What If Your Car Jerks Forward Without a Check Engine Light?

Bad spark plugs, clogged injectors, vacuum leaks and plenty of other issues might be enough to cause your car to jerk forward without a check engine light.

It could also mean you have something on your vehicle out of spec or place just enough to affect your performance, but not enough to be picked up by your car's sensors.

Diagnosing the Problem

1. Check Engine Light

Reading Diagnostic Codes: When the check engine light comes on, it means that the vehicle's onboard diagnostics system has detected a problem. Using an OBD-II scanner, you can read the diagnostic trouble codes (DTCs) to identify the specific code being thrown. Many auto parts stores offer free code-reading services, or you can go to us for a free reading as well as an estimate.

Common Codes Related to Jerking: Some common DTCs related to car jerking during acceleration include P0300 (cylinder misfire detected), P0171 (system too lean), and P0420 (catalyst system). Understanding these codes can help you pinpoint the cause of the problem and take appropriate action.

2. Visual Inspection

Fuel and Ignition Components: A visual inspection of the fuel and ignition components can reveal obvious issues such as damaged spark plugs, worn ignition coils, or a clogged fuel filter. Checking for loose or corroded connections can also help identify potential problems.

Transmission and Air Intake System: Inspecting the transmission fluid, as well as the air intake system parts, can help identify issues such as low fluid levels, dirty filters, or damaged sensors. Fixing these issues can prevent further damage and improve vehicle performance.

3. Professional Diagnosis

When to Seek Expert Help: If you're unable to identify the cause of the jerking or if the problem persists after addressing the common issues, it's time to seek professional help. Our certified mechanics have experience and the tools to tackle anything you need. Take one look at our reputation and you'll see you're in good hands.

Solutions and Preventative Measures

1. Regular Maintenance

Scheduled Service Intervals: Adhering to the manufacturer-recommended service schedule is important for maintaining your vehicle's performance and preventing issues like jerking during acceleration. Regular oil changes, filter replacements, and inspections can keep your car running smoothly. Trust Car City Wholesale to take care of all the work required to keep your vehicle running smooth and for years to come.

2. Using Quality Parts and Fluids

OEM vs. Aftermarket Parts: Using high-quality parts and fluids is essential for maintaining your vehicle's performance. Original Equipment Manufacturer (OEM) parts are designed specifically for your vehicle and ensure optimal fit and function. While aftermarket parts can be cheaper, they may not always meet the same quality standards as OEM parts.

Fluids: While there can be many opinions on fluid weight and what is best for your specific vehicle, trusting OEM fluid weights tends to be the safest option.

Conclusion

A car jerking during acceleration can be caused by various issues including: problems with the fuel system, ignition system, transmission, air intake system, and engine components. Diagnosing and fixing these problems quickly is important for ensuring safe and smooth driving. Regular maintenance, using quality parts and fluids, and ensuring proper vehicle care can prevent many of these issues from occurring.