Car jolts on starting and sometimes is fine

Almost every time, but not all the time, when I start driving my car, there is a jolt forward, as if the engine were going or the transmission. Other times I drive and there are no problems at all. When the jolting happens, it feels almost like my car is trying to shut off. I’m thinking it might be the fuel. The filter and serpentine belt have both been replaced. It’s been 30,000 miles since I had a tune up, so I might need to get that done. What do you suggest I do to fix this?
Experienced mechanics share their insights in answering this question :
The vehicle may have more than one problem and would need to be thoroughly checked in order to properly diagnose the problem. I would recommend having a certified mechanic test the system’s computer and perform a road test to see if the problem can be isolated to the engine or transmission.

You may just have broken motor mounts or transmission mounts, these could cause jerking when accelerating. It would not cause the engine to shut off, unless the wire harness, near the firewall, is damaged by the shifting engine.

I’d recommend getting some help from a certified mechanic, they will be able to properly diagnose your cars jolting symptoms firsthand and make the necessary repairs.

How to Identify and Fix Common car Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced mechanics :

Your vehicle could have dirty fuel injectors, a damaged fuel pump, a blocked catalytic converter, a faulty mass airflow sensor, broken spark plugs, or even an accumulation of moisture.
If you`re driving at freeway speeds and notice your engine sputter or jerk, you may have a failing fuel pump. This problem is caused when the fuel pump can`t deliver a smooth flow of fuel to the engine; periodically, your engine receives only air when it was expecting to receive fuel.
Usually when the car will `jerk` when you press the accelerator and lift from the accelerator, it`s likely due to clogged fuel injectors, damage to the throttle body or other fuel system components. It could also be due to worn out motor mounts or perhaps a small exhaust leak.
Car jerking can result from issues with fuel delivery components, such as: Fuel pump: A failing or weak fuel pump can lead to insufficient fuel delivery. Fuel injectors: Clogged or malfunctioning fuel injectors can disrupt fuel atomization. Fuel filter: A dirty or clogged fuel filter can restrict fuel flow.
One of the most common causes of a sputtering engine is an issue with the vehicle`s fuel system—the filter, pump, and injectors. These three critical components work together to ensure fuel flows smoothly from the fuel tank to your engine`s fuel injectors, and then pumps into the engine evenly.
If you hear your car engine stuttering, then the injectors may not be providing an adequate amount of fuel. To fix this, you should clean the injectors on a regular basis. Using a fuel injector cleaning solution might eliminate the issue of the car jerking.
Dirty fuel injectors are among the most common reasons for why an accelerator becomes jerky. The dirty injector leads to your car losing power when you attempt to accelerate while at a stop and when you try to drive at a consistent speed. This is the result of an engine misfire.
A Transmission Fault

Shifting issues can sometimes cause your vehicle to feel like it is jerking when accelerating. If you have internal transmission damage, it can cause the gears to slip [and] engage over and over again, which feels like jerking when accelerating.

When your car jerks, stumbles or stutters while driving, it usually means something is interfering with the proper distribution and transfer of power from your transmission. Another example is if you`re driving a manual transmission and haven`t gained the feel of shifting for your particular vehicle.
An indication that a vehicle is not receiving the right mixture of air and fuel is if the vehicle jerks or surges forward at high speed. Several components of the fuel or air intake system could cause this jerking or surging sensation to happen. Issues within these systems can also cause fuel economy to worsen.
It could have a failing mass air flow sensor, a failing throttle position sensor, a problem with the fuel pressure, or even an internal transmission problem.
So, if your car starts stuttering, there`s a good chance there`s an issue with your spark plugs (or the cables attached to them). It`s not unusual for these car parts to wear out, and a faulty spark plug will cause your engine to misfire and jerk when you accelerate and for your engine to be much louder than usual.
FACT #4: YOU SHOULD CHANGE SPARK PLUGS EVERY 100K MILES OR SO. So, if good spark plugs are the key to avoiding these issues, how long do spark plugs last, exactly? The general rule of thumb about how often to change spark plugs is that they should be replaced after about 100,000 miles of driving.
Engine misfires, rough idling and hard starts can all be traced to a clogged engine air filter. The dirty air filter restricts the air supply to the engine causing unburned fuel to form a soot residue that accumulates on the spark plug.
A clogged fuel filter causes low fuel pressure that results in a lean fuel condition and engine misfire. This can result in poor fuel mileage, rough idling and possibly cause the check engine light to come on. Once that light is on, it`s time for a trip to the repair shop.
If you notice that your car jerks while you`re accelerating, this is an issue that you shouldn`t ignore. A jerking car is often a sign that your car will develop other problems if you don`t address this issue. Dirty fuel injectors are among the most common reasons for why an accelerator becomes jerky.
Typically, a car delivers a subtle rumble when at idle. If you notice that the sound has gone from low to a rough and unpleasant noise, it may be a sign of bad fuel injectors. That occurs when particles build up on the injector nozzles, thus affecting the amount of spray and atomization of fuel.
If the alternator is not charging the battery and not providing enough voltage into the system then you will get this jerking. If there is not enough power in the system, then the computer will have trouble shifting the transmission properly among other possible issues.
Dirty Air Filters

The air filter functions to prevent dirt and debris in the air from entering the engine. If it`s dirty, it could restrict airflow to the engine, thus reducing the amount of oxygen that the engine gets. This causes an uneven oxygen-to-fuel ratio in the engine which leads to misfiring and car jerking.

A bad battery can also be the cause for a car to jerk. This happens when the battery is weak. If your car`s battery isn`t sufficiently charged by its alternator, it would surely not have enough voltage to power the car and ensure smooth running.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

My car will not start Intermittently. I purchased a new battery 2 weeks ago and yesterday the car wouldn’t start. Got a jump and
ANSWER : The issue you are having is probably due to an intermittent fault in the starter motor itself or a deficiency in the starter electrical circuit, for example a large voltage drop due to a poor ground or a high resistance connection. These issues can be readily diagnosed and resolved on a mobile basis if you request a hard starting diagnostic. If you request that diagnostic, the responding certified mechanic will get this resolved for you promptly. Based on Toyota’s Factory Service Manual, the battery should not be disconnected if the vehicle engine is running. The battery acts as a large resistive voltage sink and consequently taking the battery out of the circuit, while the alternator is still running, can create a voltage spike on the car’s electrical system which is not good for voltage sensitive components such as the engine computer. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

Map sensor car won’t start up good ?
ANSWER : Your MAP sensor is an important input for your computer. It helps determine the load on the engine to calculate the correct amount of fuel to inject. It sometimes takes a few seconds for the vehicle to realize that the sensor is not producing a good signal.

At that point, it will use other methods to determine the fuel rate, such as pre-programmed fuel maps, throttle position, etc. I would suggest replacing the MAP sensor and retesting. If you would like to have it checked first, a certified technician from YourMechanic will be able to scan your vehicle and test components to determine the root cause of your starting issue before making a repair.

My car won’t start, neither does my auto. Start. Sometime it might start if I jump it sometimes it won’t.
ANSWER : Hi there. There are a number of issues that will make a car hard to start. Everything from the electrical system to the fuel system to the actual starter itself can be the problem. Finding the root cause of a hard starting engine can take some investigation. Ignoring a hard starting issue can further damage the vehicle, which will often result in a more expensive repair. You might want to have a mobile mechanic complete a car is hard to start inspection so they can pinpoint the source of the issues you’re having and recommend the right repairs be completed.

car hesitates when trying to start the car ,but when started then i shut car off and start again it will start right up
ANSWER : Hi there:

Sometimes when you have problems starting an engine initially it is caused by a restriction in fuel flow; caused either by clogged fuel injectors or the throttle body that needs to be cleaned. Once the fuel starts to flow and engine warms up, it’s much easier to start. However, it could also be an air filter, EGR valve or other components that causes this issue as well, which is why it’s best to have a professional mobile mechanic complete a car is hard to start inspection so they can pinpoint the source of this issue.

My car stutter starts, but only after driving it for a few minutes.
ANSWER : Hey there. This may also be caused by what is called the fuel pressure regulator. This is a unit that helps to maintain the fuel pressure at the proper level. When this is not working properly, the fuel pump may be pumping properly, but the fuel may not arrive at the fuel injectors at the proper psi. When this happens, this can cause a lean fuel condition which may cause the car to hesitate, misfire, or stall. If you would like to have an expert pinpoint the issue, a certified professional from YourMechanic can come to your car’s location to inspect the hard start problem and confirm which repairs are needed.

My car I have push to get it started it starts fine then when I parked up and try it later it doesn’t start my battery is fine no
ANSWER : Hello, thank you for writing in. If you are in a position of having to push start the vehicle, you need to replace your starter motor. The diesel leak may be contributing to the malfunction of the starter. If this is the case, the diesel leak will need to be resolved before the replacement is made. The diesel fuel can deteriorate and foul the electronics within the motor. The new starter will likely fail prematurely as well and it will cost you more money in the long run. Typically push starting a diesel vehicle is almost impossible, specially in colder weather. Push starting the vehicle is very hard on the engine and you should have the starter replaced as soon as possible. For more help with this repair, you may contact our service department.

Sometimes car won’t start, sometimes car starts great – 1998 Mercury Grand Marquis
ANSWER : I usually try not to split hairs when it comes to batteries. If it is 3 years old or older, and it gives you trouble, it’s most likely time to replace the battery. Load tests are okay, but do not cover all that can go wrong internally.

Did you fully charge the battery first? Does the car sit for extended periods? You may consider having a local expert check the battery with an advanced tester that will check for most problems. They can also check your alternator. A bad battery can ruin an alternator so is it really worth it? If you would like to have this checked, a local technician should diagnose your battery in person to see if it is ready to be swapped.

Charging warning light comes on when i turn the key and try to start the car and the car want start but when someone tried to give
ANSWER : Hi there:

If you recently replaced your battery, the issue may be caused by a malfunctioning alternator or other electrical component that comprises the charging system on your Nissan Sentra. The best way to find out which item specifically is faulty, is to have a professional mobile mechanic complete a car is hard to start inspection. This will allow the mechanic to determine the precise source of what’s going on with your Sentra and recommend or complete the right repairs.