Buying a car is easy, but its maintenance is the hard part. Your car requires constant attention in terms of washing, detailing, polishing, servicing, and lots more.
Article summary
Dirty injectors and car engine parts are the most common reasons that a car jerks at low or constant speeds while driving. However, some other reasons include the following:
- Spark plug issues
- Distributor caps condensation
- A new car part
Continuation
If you’re missing some maintenance pointers, your car will surely remind you in the worst ways. One of these is experiencing car jerks while driving. In this article, we lay down all the reasons a car jerks at low or constant speeds while driving.
Keep reading so you can save yourself some hassle!
Table of Contents
Reasons a car jerks driving at low or constant speeds
There could be several reasons a car jerks driving at low or constant speeds, and we cover them all below.
Dirty injectors

While cars look smooth sailing on the outside, what goes on inside the engine is beyond a layman’s understanding. But we’ll try to sum it up.
Fuel is used to power vehicles. They must burn it to create energy. However, this practice leaves the engine’s insides prone to grime and dirty leftovers from the burning. If any dirt gets on the fuel injector, it’s natural for the car to jerk.
A direct comparaison between dirty and clean fuel injectors can be seen in the following table.
Dirty Fuel Injectors | Clean Fuel Injectors | |
Function | Decreased fuel efficiency | Improved fuel efficiency |
Causes | Buildup of carbon over time | Regular maintenance and cleaning |
Repair Costs | Inexpensive if caught early | Less expensive than dirty fuel injectors |
Maintenance | Regular cleaning recommended to prevent buildup | Regular cleaning recommended to keep fuel injectors working |
Some signs that your injector might be dirty are the jerking you experience when the car is cruising at normal speeds. Another sign is the vehicle losing power while cruising.
Solution: You can avoid this phenomenon by regularly cleaning the fuel injector yourself. A car cleaning kit for the fuel injector can be bought at most garages. Buy one with PEA cleaning fluid.
Regular cleaning can avoid sky-high repair costs.
Dirty engine parts

Apart from the fuel injector, other parts could also be causing car jerks in the engine. Your fuel filter can get clogged from the burning fuel grime.
If you are somewhat acquainted with the parts of an engine, you can uninstall, clean, and refit it yourself. But you should call a professional if you are a first-timer.
It might help to give the engine a good cleaning once in two or three months. Exceptionally dedicated drivers do this because they know the benefits. It doesn’t hurt to start now if you haven’t already!
Spark plug issues

If the car jerking is happening just as you start driving, the issue could be with the spark plug. Imagine you pushing a lighter that sparks a flame, which you use to light a candle.
It is somewhat the mechanism of a spark plug. The most common issues with spark plugs are shown in the following table.
Issue | Symptoms |
Buildup of carbon or oil | Engine misfires and poor acceleration |
Gradual erosion of the electrode | Reduced fuel efficiency and decreased power |
Overheating of the spark plug | Engine knocking and difficulty starting the engine |
Oxidation of the spark plug | Poor acceleration and engine misfires |
The battery is used to ignite the spark plug. In turn, it ignites the fuel. The fuel starts burning, and the car comes into motion.
But if the spark plug is dirty or faulty, this can’t happen. You’re expecting an unlit lighter to light a candle.
There are several spark plugs. Some may be working while others aren’t. However, if you replace some and leave others, you might encounter the same problem again. The older plugs will stop working while the new ones stay intact.
That’s why you should consider replacing all the spark plugs at once. However, do check once to see if cleaning them will do the trick.
Signs to look out for
First off, let’s learn how to recognize car jerking. If you’re driving normally at constant or low speeds and experience a motion forward that can only be explained as if you just hit the gas and let go suddenly – that is a car jerking.
There can be several reasons for this, but you must identify the frequency and the circumstances of the jerking. Does it happen when you speed up? Does it happen when you start the vehicle?
Does it randomly happen as you drive at a uniform speed and catch you off guard? The answer has a lot to do with the solution.
At a constant speed
Sometimes you don’t even hit the gas, and the vehicle seems to have a mind of its own, and the car jumps. We cover some of the reasons for this below.
Condensation in distributor caps

If you live in colder areas, parking a vehicle overnight could cause moisture to form inside distributor caps. Water might seem harmless, but it can cause engines to misfire when accelerating at low speeds.
You can park your vehicle in a garage or porch area to avoid this. If this is not possible, you could buy a thermal cover easily. It will ensure your vehicle stays protected from any additional heat and damage as well.
Engine mounts coming loose
The engine mounts keep the chassis connected to the engine. Sometimes this can get worn out and disconnected. When engine mounts come loose, it causes your engine to rev at lower speeds.
If this certainly is the case, it might need replacement. Only get this done by a trusted and qualified professional as the engine will need due support from beneath during the job- it certainly isn’t an amateur task!
Fuel running out
We’ve got some good news and bad news. The good news is that there might not be anything wrong with the car.
The bad news is that you forgot to feed it, and now you must fetch some fuel for it to start again. Thankfully the car isn’t like a pet that reacts dramatically to a feeding being missed.
But this might mean you are getting stranded in the middle of nowhere with no gas for miles. So always pay attention to the fuel meter before going on long drives.
A new part
You left your car at the garage for servicing, and now that you’re driving off after retrieving it, it feels different. Sure it is shiny and new-looking. But the smoothness of the drive isn’t the same.
A new installation could be a problem if the vehicle stutters and spurs when stopped or accelerating.
You’ve got new parts installed like new spark plugs or a rack and pinion steering, and the car is jolting with a mind of its own.
We recommend you head to a trusted mechanic (a different one) and get the work checked steadily.
If the new parts are not installed properly, they could cause malfunction. They could even result in other parts of the car being damaged.
Some fluid under the car
Are you noticing some unwanted red fluid under the car? The Check Engine light is also on and stays on. That’s exactly what you need to do.
Get the vehicle checked by a professional mechanic. Loose bolts and unhinged drain plugs as well might be causing the leaking of the transmission fluid. It will cause the car to go into jumping mode occasionally.
Here are some properties of the transmission fluid.
Benefit | Description |
Lubrication | Helps lubricate various components of the transmission |
Cooling | Helps cool the transmission and prevent overheating |
Cleaning | Transmission fluid contains additives that help to clean the transmission |
Seal protection | Keeps the seals and gaskets soft and pliable |
Your engine will be stuttering, spurting, and not working at its best until you get this fixed.
Keeping the transmission fluid intact will cause the engine to work at its prime. It will also increase the life of your ride by several years!