A juddering or jerking car can be a driver’s worst nightmare, but why does your vehicle do this?
Here we look at the most common reasons why your car is juddering, stuttering and jerking both idle and moving, and how you can fix the issues.
Why is my car jerking when I accelerate?
Unfortunately, there are a number of reasons as to why your car may be juddering when you accelerate, rather than a one-size-fits-all explanation. These are the most common causes:
Fuel injectors
If your fuel injectors are dirty or they are malfunctioning, it can disrupt the delivery of the fuel and often result in vehicles stuttering at low speeds.
Fuel filters
Having a clogged or worn-out filter will impact the fuel delivery, causing performance issues when driving slowly.
Spark plugs
Your car may jerk when accelerating due to a defective spark plug, which causes the engine to misfire. This is often caused by worn-out spark plugs or their electrical cables. If you have the knowledge, you can change the spark plugs yourself, but if you are not qualified to do so, it is best to get a trained mechanic to help.
Transmission fluid
Old or contaminated transmission fluid can affect acceleration. This happens when the fluid degrades or becomes contaminated which will affect its ability to lubricate and cool the components effectively.
This can then lead to issues such as slipping gears, delayed acceleration and hard shifting which affects the car’s performance.
Catalytic converter
Another cause for your car jerking during acceleration could be a clogged catalytic converter. A blockage here can disrupt the exhaust system’s airflow, leading to a noticeable delay in your car’s response when you press the accelerator. You might also detect a rotten egg smell. For exhaust repair, you may need to call for assistance.
A good catalytic converter cleaner will help to unclog any minor blockages that you may have. However, if it is a major clog, you will need to seek expert assistance.
Why is my car juddering or stuttering when pulling away?
If your car is juddering when you’re pulling away from being stationary, it’s highly likely you have an issue with your clutch.
Worn-out friction material or a pressure plate deficiency, or sometimes a combination of both, can be the cause. If it’s neither of these, it could be an oil leak, which is contaminating the clutch plate.
Clutches should not be worked on by untrained professionals; you should seek out a local garage for this specialised repair.
What causes my car to jerk when accelerating at low speeds?
Just like with acceleration problems, there are a few reasons why a car can be jumpy with low revs.
Engine mounts
Engine mounts hold the engine in place to the chassis, which is why if there’s an issue with them, the car starts to jump.
If one of these is loose, the vehicle will start to vibrate even on low revs. If this is the case, you will need to get this fixed by an approved mechanic.
Issue with your distributor cap
Moisture in this cap will cause the car to stutter when you’re trying to accelerate at low speeds. This is caused by condensation forming inside the cap, meaning the engine is misfiring. Surprisingly, this happens when parking your vehicle overnight in cold temperatures outside.
A simple solution to this is to park your car in a garage if you have one. If you have to park outside, you can purchase a thermal cover to reduce the risk of condensation.
Why does my car shake when idle?
If your car is juddering when you stop at junctions, turns and traffic lights, it will be more likely to stall and cause you some serious issues when driving.
This is usually caused by the spark plugs being faulty or a major build-up of dirt.
A shaking or juddering car can stem from several issues related to fuel and engine health. If the juddering occurs specifically when the car is idling, it might indicate a minor vacuum leak within the engine or a faulty electrical part, such as the crankshaft sensor.
A vehicle’s engine can shake or shudder, particularly when idling, due to several factors beyond the idle itself. A common cause is a restricted fuel or oxygen supply to the engine, often a result of a clogged fuel filter or injection system. Additionally, as a car accumulates mileage, wear and tear can lead to sludge buildup that obstructs the engine’s valves. This blockage disrupts the consistent and clean fuel distribution essential for smooth operation, causing the engine to judder and shake.
If you’re not a mechanic, you should not attempt to fix or replace any of these components yourself. There is a way you can help prevent yourself from having this issue. You should regularly check your engine for signs of dirt that could clog up the system, and make sure the car is serviced every 10,000-12,000 miles.
Occasionally, things do go wrong while you’re out on the roads, so be sure to have the correct breakdown cover in place just in case.
Why does my car judder when braking?
Cars usually judder due to two main reasons: issues with your brake pads or your brake discs.
Brake pads can either be worn down or become faulty, which will result in a juddering sensation when applying your brakes. This is usually from wear and tear and can be common in older vehicles.
In regard to your brake discs, these can develop an uneven thickness, which results in your car stuttering. Brakes need these to run smoothly, and in order to do so, they need a uniform thickness to avoid unwanted friction. Any misalignment will cause vibration and lead to poor braking performance.
You can clean the disk and the surrounding surface in order to combat this, but this is only a temporary solution, and they will need replacing. A damaged disc can be extremely dangerous and should be replaced immediately.
Why does my car stutter when changing gears?
Clutch issues can cause your car to stutter when shifting into first gear; this is most likely due to a pressure plate problem.
A leakage in the clutch system may contaminate the clutch plate surface, causing a stuttering or juddering feeling when accelerating.
Low or contaminated transmission fluid can cause juddering during gear changes. Additionally, a faulty sensor or an issue with the gearbox vacuum could be the cause of the problem.
Why is my car juddering when driving?
Issues with your car’s wheels or tyres can cause shuddering. This includes incorrect tyre pressure or balance, which can also lead to uneven tyre wear.
Additionally, over time, improper tyre pressure or balance can cause lug nuts to loosen, further contributing to shuddering.
To address these issues, consider having your vehicle’s wheels realigned or your tyres replaced.
Car insurance with Sterling
Whether your car is juddering or not, you’ll need the right insurance. That’s where the experts at Sterling can help you out.
We tailor car insurance policies that are right for you, no matter your circumstances. We also offer breakdown cover at affordable rates.
Get a quote by calling us on 0344 381 9990 or request a callback at a time that suits you.