Car Jerks When Accelerating? What It Means & What You Should Do

When you wake up in the morning, jump in the car, and turn it on to go to work or school, you expect to just push on the gas pedal and get things rolling. The last thing you expect is for some unpredictable problem to rear its ugly head and leave you running late.

Cars were designed to get us to our destinations in comfort and reliability, but that doesn’t happen all the time.

One of the most obvious signs of trouble is if your car isn’t accelerating smoothly.

Though this doesn’t always signify a major issue, it’s a red flag that warns you that one is sure to occur in the near future. 

In this post, we reveal how you can find out what this problem is and fix it before any more damage is done to the vehicle. 

12 Reasons Why You Have Jerky Acceleration (and How to Fix It)?

As mentioned above, there are several reasons why your car might be jerking when you accelerate. Below, we’ve listed the 12 most common.  

Reason 1: Dirty Air Filters

If your car jerks upon hitting the gas due to a clogged air filter, you’re in luck.

The air filter would have to be seriously clogged and neglected to reach the point where it causes your vehicle to jerk during acceleration. Despite this, needing only a filter change is the easiest of problems to face.

Depending on your vehicle, air filters can cost as little as $15, and they’re very easy to check and replace.

Here’s What You Can Do

Replacing the air filter is one of the easiest and cheapest maintenance tasks you can perform yourself. Having a mechanic do this for you might be a better option, though, if you’re already having other things done to your vehicle.

If this is the only issue, it’s a waste of time to schedule an appointment to have this fixed. Simply take the old one out (opening the hood and follow the airflow tubing from the engine to the filter), throw it away, and install the new one.

It’s a pretty easy and straightforward task, so there’s not much that could go wrong. Just make sure you get the right kind of filter as specified by your owner’s manual.

Reason 2: Fuel Lines Are Clogged or Damaged

Fuel lines deteriorate and get clogged over time. They can even be damaged by rodents or other creatures if you leave your vehicle out at night or live in a rural area and don’t drive it much.

Fuel starvation occurs when clogged or leaking fuel lines prevent the necessary amount of fuel to be delivered to your engine’s combustion chamber. The same can happen if the fuel pump in your vehicle is starting to fail, but this will more likely cause the vehicle to stall or not start properly.

Failing to address this issue can result in your vehicle stalling completely. At worst, damaged fuel lines can cause an engine fire, especially if the damaged lines are located within the engine bay, as fuel can drip onto hot surfaces and ignite.

Here’s What You Can Do

You can inspect the fuel lines by taking a peek underneath your vehicle and inside the engine bay.

If you see any signs of damage or corrosion, you’ll either have to replace them or have a mechanic do so.

If you don’t see any signs of damage, you can release the clamps along the fuel lines and use a pipe cleaner or instrument cleaner to remove any obstructions along the lines.

Reason 3: Fuel Filter Needs To Be Replaced

Any kind of dirt that gets in your fuel tank can cause obstructions throughout any part of the fuel delivery system. Sediment from the fuel chambers at gas stations can sometimes enter your gas tank when refueling.

If this occurs, the issue is most likely from a clogged fuel filter that needs to be replaced, as it’s failing to trap any dirt and sediment traveling through the system.

Here’s What You Can Do

Replace the fuel filter. New ones usually aren’t too expensive and you can generally do this yourself.

Simply refer to the owner’s manual to see the specific type of filter needed for your vehicle.

If dirt has gotten into the injection system, it wouldn’t hurt to perform an injection system flush to make sure everything is properly cleaned. 

Reason 4: Faulty Spark Plugs

Spark plugs are responsible for creating the bang within the combustion chamber that pushes the pistons down and makes power.

If they’re clogged with carbon buildup or there is oil leaking onto the spark plugs, the electrical current won’t be able to flow and no spark will be created. This ends up causing a misfire and your car jerking when accelerating, or even total power loss.

Here’s What You Can Do

Changing the spark plugs should be part of your regular maintenance routine, and you can definitely do this yourself. 

You won’t have to replace them as often as the engine oil, but they will have to be replaced several times during your vehicle ownership.

Reason 5: Damaged Acceleration Cables

Most modern vehicles won’t have this issue because of the drive-by wire systems that control everything through the ECU, but many older vehicles have a physical accelerator linkage.

If this linkage between the engine throttle plate and gas pedal has become worn or damaged, it can make your car jerk and will need to be replaced.

Here’s What You Can Do

You can examine the accelerator linkage by opening the hood, finding the linkage connecting the throttle to the accelerator, and checking it.

Most people that experience this issue will know how to replace it themselves, as this system is very nearly defunct in most modern vehicles. Still, replacement costs are low.

Sometimes, the solution to this is even as simple as reconnecting the linkage if it has become loose.

Reason 6: Dirty Fuel Injectors

A common issue with direct injection vehicles is carbon buildup from the combustion occurring within the engine.

Clogged and dirty fuel injectors are some of the most common problems associated with weak or jerky acceleration, as engine misfires can develop from fuel not reaching the combustion chamber.

Note: If you suspect a dirty fuel injector to be the issue, you should check out our guide to the best fuel injector cleaners, and instructions on how to clean fuel injectors.

Here’s What You Can Do

Tearing apart the engine to clean fuel injectors is something that will require a mechanic. However, before jumping to that, have a mechanic flush the fuel injectors, which could save you a larger bill. This usually costs less than $100.

Reason 7: Distributor Has Moisture Issues

Another largely defunct issue that may cause jerking during acceleration is moisture accumulation within the distributor.

The distributor is responsible for the spark timing within the engine.

Weather can cause temperature fluctuations responsible for excess condensation within the distributor, which will prevent the spark from firing in the car’s engine. This results in a misfire and your car jerking upon acceleration.

Here’s What You Can Do

Similarly to the accelerator linkage, distributors have been largely phased out in favor of electronic ignition timing.

People with vehicles containing a mechanical distributor will most likely understand how to troubleshoot in regard to this issue.

Carburetor cleaner and trying to regulate the environment – perhaps parking in a garage – are two ways to fix or even prevent this issue from happening in the future.

Reason 8: Clogged Catalytic Converter

The catalytic converter takes the harmful exhaust gasses produced by the engine, catalyzes them, and makes them less harmful to the environment.

Over time, your car’s catalytic converters will become clogged and will prevent optimal airflow through the exhaust system, which could lead to a jerking car during acceleration.

Here’s What You Can Do

If you have a blocked catalytic converter, it may cause the check engine light to come on. This is actually good news, because a catalytic converter issue is one that might otherwise be more difficult to diagnose.

A replacement catalytic converter is fairly expensive and should be only completed by an auto repair shop.

An OBD II scan of the vehicle will usually alert you to a problem.

Reason 9: Alternator Needs To Be Replaced

The battery is the primary source of energy for actually starting your vehicle, but the alternator circulates electrical power throughout most of the vehicle’s systems while it’s running.

If the power supply is low or power isn’t circulating correctly, systems like the fuel pump and electronic fuel injection won’t receive enough voltage to work correctly. This can lead to your car jerking when accelerating.

Here’s What You Can Do

Changing an alternator can be simple if you’ve ever worked on other vehicle systems before.

You will have to loosen and remove the serpentine belt (which sometimes requires a special tool) – but other than that, it’s as simple as removing wiring harnesses, removing bolts, and replacing the part.

You will have to buy the correct alternator specific to your vehicle, though, and consulting your owner’s manual will always guide you in the right direction.

Reason 10: Engine Tuning Is Off

This is rarely a problem with most modern cars because the ECU is becoming so advanced and can adapt to changing conditions easily.

However, if you have recently had your ECU replaced or you place aftermarket parts on your vehicle, you may need a tune-up so that your engine runs optimally.

Here’s What You Can Do

If you know what you’re doing, you can buy programs that help you perform a tune-up all by yourself.

However, and this applies to most people reading this, you will most likely have to take your vehicle to a special shop to have this done correctly.

Reason 11: Transmission Fluid Is Low

Transmission fluid is essential to help your vehicle shift gears. When it’s running low or there happens to be a leak, fluid won’t be able to reach all of the necessary crevices and gears and could cause jerking when accelerating.

Here’s What You Can Do

You can check the transmission fluid levels in your vehicle by pulling out the transmission fluid dipstick similarly to how you check the oil in your engine.

If levels are low, try filling it up little by little until it reaches the markings on the bottom of the dipstick.

If the problems still persist, it may very well signal a different kind of transmission problem.

Reason 12: Clutch Is Slipping or the Transmission Solenoid Needs To Be Replaced

If you have a manual transmission vehicle, the jerking could signify a slipping clutch as its material wears down over time. 

If you have an automatic transmission, jerking while accelerating may be a sign of a transmission solenoid issue. The solenoid is electronically controlled by the transmission control module to help an automatic transmission choose the right gear for your car by using the fluid in the transmission itself. 

Here’s What You Can Do

If the issue turns out to be a clutch or solenoid problem, the transmission will need some serious work done on it.

Both clutch and solenoid replacements are among the costliest of vehicle repairs, and will need a professional mechanic.

For more tips on how to check for jerking, hesitating, and lurching issues, check out the following video.

What Does It Mean When My Car Jerks?

Most of the time, if your car shakes while hitting the gas, there’s a problem in one of four main areas of the vehicle.

The Transmission

The transmission is what transfers power from the engine to the driving wheels of the vehicle. If there are any issues with this system, the vehicle could jerk forward or not be able to move at all.

The Ignition/Electrical System

The ignition system is responsible for giving your vehicle’s engine the spark it needs to combust the air-fuel mixture in the cylinders, and ultimately make the car move forward.

A disruption in the electrics of a vehicle could cause jerking and lurching during acceleration.

The Fuel System

If fuel can’t get to your engine, it won’t be able to turn over and move the vehicle.

If there’s something blocking the fuel system or fuel starvation occurs, it’s common to have jerking during acceleration.

The Air Induction System

Problems with air induction are less common causes of cars jerking during acceleration, but are much easier and cheaper to fix.

Just like the fuel system, any blockage of air to the engine will cause it to hesitate, jerk, and is a likely reason why your car stalls while driving.

How Do I Know Where To Look For The Issue?

Understanding that there could be several reasons why your car jerks, you now need to know where to start so you can diagnose and fix the problem.

OBD II Scan Tools

If your engine is accelerating slowly or jerking, and the check engine light is flashing (or just on), the easiest and quickest way to diagnose the issue is to scan it with an OBD II scan tool.

OBD II (onboard diagnostics computer) has been mandated on vehicles since 1996, and it’s the universal system that tells the scanner what error codes are being produced by the vehicle’s computer system.

Many vehicle parts stores offer scans for free, and every maintenance shop will have these scan tools readily available. You can even buy one yourself, of course – check out our guide to OBD-II scanners if you’re keen to do so.

System Inspections

Another way to diagnose an issue is to do a quick visual inspection of all the systems that could be problematic. This is helpful when you know there’s a problem, but the “check engine” light isn’t illuminated.

You can easily check things like the fuel line, air filter, and spark plugs just by examining them. Any obstructions, damage, or leaking will most likely lead you right to your problem.

What Could Happen If I Don’t Fix A Car That Jerks When Accelerating?

As with anything else, if you just ignore the problem, it isn’t going to go away. Not fixing the issue right away may not be completely detrimental in all cases, but at the very least, the problem will persist and won’t go away on its own until you address it.

More likely, the issue will become worse with time and possibly cause your vehicle to stop running altogether, or could even cause an accident or fire in the most severe of situations.

Wrapping It Up

Some of the issues we’ve discussed in regard to jerking during acceleration are common problems of the past, such as the distributor moisture and accelerator cable.

Most others involve simple and inexpensive fixes, and can often be prevented with a regular maintenance schedule that you stick to.

Still, if your car should ever experience any jerking during acceleration, don’t leave it unattended and assume that the problem will solve itself on its own in time. It won’t!

For now, rest assured that you now have a comprehensive overview of what to look for and how to rectify the situation should an issue arise.