Imagine this: You’re cruising on the highway, and as you hit the gas pedal to accelerate, your car starts to jerk.
At that moment, you probably ask yourself: why does my car jerk when I accelerate?
And how can I fix it?
We’ll answer these questions for you.
Keep reading to discover 10 potential reasons your car jerks when you hit the gas pedal and the steps a mechanic will take to fix the issue for a smooth driving experience.
This Article Contains:
- 10 Potential Reasons Your Car Jerks When You Accelerate
- How to Fix Car Jerking Issues
- 3 FAQs Related to Car Jerks
10 Potential Reasons Your Car Jerks When You Accelerate
Car jerking issues stem from faults within your fuel, ignition, and transmission system.
Here are the 10 most common reasons for car jerking:
1. Dirty Fuel Injectors
A dirty fuel injector restricts the fuel flow to the engine cylinders, creating an uneven fuel-air mixture within the combustion chamber.
When you drive at a high speed, your engine requires more fuel. Dirty fuel injectors can mess up this accelerated combustion requirement, causing the engine to misfire or the car to jerk.
Note: Car jerks can also result from a damaged fuel line or defective carburetor in older cars.
2. Faulty Spark Plugs
A spark plug gets damaged by excessive heat or issues with fuel ignition timing. This can lead to erratic power delivery and diminished vehicle performance.
As a result, damaged spark plugs can make your car jerk at high speeds or take longer to respond when you press the gas pedal. They might even cause your car to stall or fail to start.
3. Low Engine Oil Levels
Engine oil lubricates the engine’s moving components to ensure smooth operation. When the engine oil level is low, increased friction between critical parts can affect engine performance and cause jerking.
Remember: Low oil can also make your engine overheat, resulting in expensive repairs. So watch out for a low oil level warning on your dash.
4. Dirty Air and Fuel Filter
A clogged air filter restricts the airflow to the engine. This creates an air-fuel mixture imbalance and disrupts combustion, making your car struggle at high speeds.
Similarly, a dirty fuel filter obstructs the flow of clean fuel to the engine, resulting in inconsistent fuel supply, erratic engine performance, and car jerks.
5. Clogged Catalytic Converter
The catalytic converter (CAT) converts toxic substances into less harmful gases to reduce the amount of pollutants exiting the exhaust system.
If the air-fuel mixture in your car is overly rich, it can result in a clogged catalytic converter. A clogged CAT can trap harmful gases and disrupt exhaust flow, making the car stutter or jerk.
6. Faulty Mass Airflow Sensor
The MAF sensor measures the air entering the engine and shares this data with the Engine Control Unit (ECU). The ECU uses this data to adjust fuel injection and ignition timing. Malfunctioning sensors can give inaccurate readings to the ECU, disrupting the fuel supply to the engine and causing jerky acceleration at high or low speeds.
7. Defective Throttle Position Sensors (TPS)
The throttle position sensor monitors the position of the throttle valve. It sends this data to the ECU and uses it to adjust the air-fuel mixture and ignition timing. A faulty TPS can send the wrong data to the ECU, resulting in an imbalanced air-fuel mixture. This inconsistency makes the car’s engine hesitate or jerk at a high speed.
8. Damaged Acceleration Cable
While modern cars use electronic throttles for acceleration, older vehicles rely on an accelerator cable that connects the gas pedal to the throttle plate. Cable damage can cause the throttle valve to open partially or get stuck. As a result, your car hesitates or jerks while accelerating at a high or low speed.
9. Low Transmission Fluid
Transmission fluid lubricates components like gears, clutches, valves, and the torque converter. If the fluid level is low, these components won’t get adequate lubrication, leading to transmission overheating, gear slipping, and vehicle jerks.
10. Damaged Engine Cylinders
Car engine cylinders are crucial for power generation. If one or more cylinders are damaged, the combustion process gets compromised, leading to an engine misfire. This results in uneven power delivery to the wheels and manifests as jerking.
So, how do you fix a jerking car?
Find out next.
How to Fix Car Jerking Issues
Since the issues behind car jerks can be complex to fix, it’s best to let a professional handle it.
A mechanic will use an OBD-II scanner to retrieve check engine light codes from the car’s computer to identify the components or systems causing acceleration issues.
Next, they’ll perform one or more of the following system checks to address the problem.
- Ignition system check: They’ll inspect the ignition system for a faulty spark plug, ignition timing, ignition coil, etc, and replace them.
- Fuel system check: They’ll inspect the fuel line, replace a clogged fuel injector, install a new fuel filter, and fix any issues with the fuel tank, fuel pump, or defective carburetor.
- Air-intake and exhaust system check: They’ll inspect the air intake and exhaust system for leaks, a blocked catalytic converter, a dirty air filter, or a faulty mass airflow sensor.
- Transmission system check: They’ll replace a damaged acceleration cable and test the TPS to check its voltage.
- Engine compression check: They’ll examine engine components like cylinders, valves, etc., to see why your car hesitates when accelerating and perform a car engine repair (if necessary).
Finally, the mechanic will take a test drive to ensure the issue has been resolved successfully.
Now that we know the causes and fixes of car jerking problems, let’s address any additional doubts you may have.
3 FAQs Related to Car Jerks
Here are the answers to some common queries about a car jerking during acceleration:
1. Is it Safe to Drive if My Car Jerks When I Accelerate?
No, you shouldn’t drive your car if it jerks during acceleration or at low speeds.
The jerking motion could indicate minor issues like a dirty air filter or severe problems like a blocked catalytic converter and transmission damage. It’s best to get a car service to fix jerking issues, as ignoring them can degrade engine performance and warrant expensive repairs.
2. Can Worn-out Tires Cause My Vehicle to Jerk?
Yes, worn-out tires can cause jerky acceleration.
As tires wear down, they lose grip on the road, resulting in the wheel slipping or spinning during acceleration. They can also cause wheel balancing and alignment issues, increasing car jerking as you accelerate.
A regular car service ensures your tires remain properly inflated and have a good tread depth for a smooth and safe driving experience.
3. How Much Does it Cost to Fix Car Jerking Problems?
The cost of repairing the parts that lead to a jerking car can vary depending on the specific problem, your car’s model, and local labor costs.
Here’s the estimated cost of fixing some of the related parts (including labor):
- Air filters: $20 to $50
- Spark plugs: $100 to $500
- Accelerator cable: $100 to $300
- Fuel filter: $120 to $200
- Throttle position sensor: $200 to $500
- Mass airflow sensor: $200 to $500
- Fuel pump: $400 to $800
- Fuel injector: $800 to $1500
- Catalytic converter: $900 to $4000
Keep Your Ride Jerk-Free with AutoNation Mobile Service
Car jerking during acceleration is a concerning issue that should be addressed promptly. Ignoring it may lead to severe vehicle damage and an expensive car engine repair service. Also, it’s best to avoid driving until a qualified auto repair mechanic fully resolves the issue.
So why not have a mechanic from AutoNation Mobile Service come to you?
We’re a mobile auto repair service available seven days a week, offering upfront pricing, convenient online booking, and a 12-month, 12,000-mile repair warranty.
Contact us to have our mechanics fix any automotive issue from your driveway!