Driving should always be smooth. If your car jerks when slowing down and you are sure about your driving skills, there can be some issues with the vehicle itself.
It’s very common to face issues related to smooth and seamless driving. When you notice jerks, especially when you slow down its speed, the shaky jerks and vibrations can indicate the fault in one of the components.
For example, when the car brakes pads are worn-out it can let out issues like that. The reason is worn out brake pads can cause clippers to grab the rotors roughly which ultimately results in jerking of the car when you slow down.
However, there are many more reasons for it. In this article we will find out the common reasons and the possible solutions.
Why Does Car Jerk When Slowing Down?
When you decrease the speed of your car it should not jerk at all. But when it does it can be due to leakage in the transmission especially if the vehicle jerks when you slow down at 25 mph.
Other reasons can be worn out clutch, damaged coil packs, damaged turbo, worn engine mounts, and a poorly timed gear shift, clogged fuel injector, defect in the mass air flow meter MAF, bad throttle body.
Let’s look at other possible reasons that make your car jerk while slowing down its speed.
9 Reasons Why Car Jerks When Slowing Down
Below are the possible reasons and solutions to the jerking car!
1. Low fluid level or Leaking of Faulty Transmission
Defect or faulty transmission has a direct impact on a car ‘s smooth drive. If the transmission features leakage it can result in visible jerks to the car.
The car transmission is for shifting gear while you accelerate or de-accelerate the speed. During downshift, faulty transmission can cause jerks.
If not leaking, the faulty transmission can be when the fluid is too low. The lack of lubrication means too much friction in the gearbox and the faulty torque converter is another that can lead to jerks while you slow down the car.
Solution
Make sure the transmission fluid is on the right level. If that’s not helping, take your car to the mechanic to get the transmission service down. The mechanic may replace it if the damage is irreversible.
2. Bad Fuel Injectors
Clogged or problematic fuel injector is another common reason. When the fuel injectors have excessive fuel or maybe too little fuel it can cause jerks in the car when you slow down the speed. If the level of fuel is good, the reason can be clogged injectors with dirt, grim and debris in the filter.
Solution
Always keep the fuel injector clean and don’t let the dirt accumulate there. However, also get the engine checked if you see the warning light come lit. Consult a mechanic to properly diagnose the problem.
3. Damaged Mass Air Flow Sensor (MAF)
MAF is responsible for maintaining the air that goes to the engine and helps to keep up the balance in the engine control unit ECU.
So when the Mass Air Flow Sensor meter gets defective it fails to maintain the air flow and results in imbalance and poor combustion. Sometimes the MAF just has blockage.
Solution
Figure out the problem and take your car to the professional car mechanic. If the MAF sensor is blocked by debris, clean it. You may need to replace the MAD sensor if its faulty itself
4. Worn Out Clutch
When the clutch is worn-out due to durability limit or over-usage, it results in the very problem. The clutch is to connect the engine and transmission in the car so that the speed remains under control. The worn out clutch means no maintenance of speed at all due to roughness in gear shift.
Generally, you should replace them after about 150,000 miles.
Solution
It’s very obvious that a worn-out or excessively damaged clutch should be replaced with now one to maintain performance.
5. Faulty Throttle Body
Another reason when a car jerks when you slow it down is due to bad throttle body which makes the performance with air intake to the engine. When the throttle body is broken, defective or leaking, you experience jerks in the car while de-accelerating it. The reason is poor control of the air supply to the engine.
Solution
Rush to the mechanic before the damage is irreversible.
6. Problem with the set of Ignition Coil Packs
If the above problems are not relatable then the faulty ignition coil pack can be the reason why the car jerks when slowing it down. Ignition coil acquires power from the car battery and changes it into the spark for starting the engine. When a car jerks or even misfires when you slow down its speed, it means the coil packs are damaged.
Solution
There is nothing much you can do except to replace the faulty ignition coil packs. You can take the vehicle to the mechanic to confirm the problem.
7. Poorly Timed Gear Shift
You don’t always have to worry about the deep car mechanic issues. Sometimes the car jerks when you slow it down because of bad gear shift timings. The poor gear shift time results in the jerks in the car. If your car is manual you will likely o face this issue.
Solution
Acquire the best driving skills especially on a manual car and drive like a pro!
8. Worn Engine Mounts
In cars the engine mounts make sure the engine is in the proper place and don’t shift the position. But when the engine mounts get damaged or broken, you notice jerks in the car because then the engine moves and can touch other components.
Solution
Replace the engine mounts and make sure its proper fixing.
9. Damaged Turbo
Broken or damaged turbo ultimately causes the car to jerk while you slow it down. The reason is your car cannot keep up with the normal behavior due to bad turbo and its impact on smooth driving.
Solution
Replace the bad turbo or repair it if it can be. Usually the repairing of a turbo is much more expensive than replacing it.
Conclusion
Before you rush to replace any of your car components, always be mindful about the problem, pay heed to the sound and the jerk frequency. If you are also noticing a squeaking sound there can be some issues with the brakes.
However, you should never continue driving if your car is malfunctioning and not keeping up with smooth drive. I can be dangerous! Call a mechanic for a professional and proper solution.
FAQs
Can I drive when the car is jerking?
Although you can drive if your car is jerking few and far between but if the intensity of jerks is high you should avoid driving it for sure. It’s important to note the intervals of jerks. If jerks are impacting the speed, consult the mechanic.
Why do cars jerk while driving?
There are a number of reasons to why car jerks while driving such as
- Dirty fuel injector
- Damaged fuel pump
- Blocked catalytic converter
- Faulty mass airflow sensor
- Broken spark plugs or even an accumulation of moisture