Car not starting is an annoying experience most of us have received our peak share. The worst of all is to have your car die while driving it on the highway or on a crowded street. This is a common experience for many drivers, which happens when least expected.
The common reason a car shuts off while driving and won’t start is a low fuel pressure caused by a weak fuel pump. However, several other things can be the culprit. The best solution is to diagnose the vehicle to pinpoint the exact problem and fix it.
In this article, I will explain these reasons, what to do if your car dies while driving and won’t start, and how to fix it. You will also learn what to do to minimize this situation from occurring.
What Would Cause a Car to Die While Driving And Not Start?
Several factors like low fuel, bad fuel pump, faulty car battery, and low charge alternator are the top reasons a car dies while driving and won’t start. Any of these issues will keep you stranded on the road.
Let’s examine these causes one by one.
#1. Faulty Crankshaft Position Sensor.
The crankshaft position sensor is essential to a car’s engine management system. It is responsible for monitoring the speed and position of the engine’s crankshaft, which helps to ensure that the engine’s fuel injection and ignition timing are properly synchronized.
This sensor uses magnetic fields to detect the rotation of the crankshaft and sends signals to the car’s computer system to make adjustments as necessary. If the crankshaft position sensor becomes faulty, it can cause the car’s engine to stall unexpectedly while driving.
This happens because the car’s computer system cannot accurately detect the position and speed of the crankshaft, which can lead to incorrect fuel injection and ignition timing. In some cases, the engine may be unable to start at all.
#2. Fuel Pump Issues.
The fuel pump delivers fuel from the gas tank to the engine’s fuel injectors. It is an essential component of a car’s fuel system and ensures the engine receives the required fuel to operate.
If the fuel pump is not working correctly, it can cause the engine to stall while driving. If the pump is not delivering enough fuel to the engine, it can cause the engine to run lean, resulting in stalling.
The fuel pump may sometimes stop working, causing the engine to stop running. Other signs of a failing fuel pump may include difficulty starting the engine, sputtering or hesitating while accelerating, and reduced fuel efficiency.
#3. Clogged Fuel Filter.
The fuel filter filters out impurities and contaminants from the fuel before it reaches the engine.
Over time, the fuel filter can become clogged with debris, dirt, and other pollutants, restricting fuel flow to the engine. If the fuel filter becomes too clogged, it can cause the engine to stall while driving.
A clogged fuel filter can cause various symptoms, including reduced engine power, hesitation while accelerating, and engine stalling. When the fuel filter is clogged, the engine cannot receive the required amount of fuel to operate correctly.
In some cases, the engine may not start at all. Regularly replacing the fuel filter is essential to ensure the engine’s proper operation and avoid unexpected breakdowns on the road.
#4. Ignition Coil Failure.
The ignition coil converts the low voltage from the battery into the high voltage required by the spark plugs to ignite the fuel in the engine.
If the ignition coil fails, it can cause the engine to stall. This can occur when the coil becomes damaged or worn over time, leading to a loss of power to the spark plugs.
When the ignition coil fails, the engine may exhibit a range of symptoms, including reduced engine power, difficulty starting, misfiring, and eventually stalling.
A weak spark from the ignition coil can cause the engine to run poorly or stall entirely. It is essential to have the ignition coil inspected and replaced to ensure the engine’s proper operation and avoid unexpected breakdowns on the road.
#5. Alternator Problems.
The alternator is a critical component of the vehicle’s electrical system responsible for generating power and charging the battery while the car runs. If the alternator fails, the battery can become drained, leading to a loss of power and eventual engine stalling.
Common symptoms of a failing alternator include dimming or flickering headlights, a weak or dead battery, and difficulty starting the engine.
One of the main reasons an alternator fails is a faulty voltage regulator, which controls the flow of electricity to the battery and the rest of the electrical system.
Over time, the voltage regulator can become damaged or worn, leading to various electrical problems and eventual alternator failure.
#6. Battery Issues.
The battery is a crucial component of the car’s electrical system that stores and provides power to start the engine and operate various electrical accessories.
If the battery is weak or dead, it may not have enough power to start the engine or keep it running, leading to stalling or failure to start.
A common cause of battery failure is age or lack of maintenance, which can cause the battery to lose its charge and ability to hold a charge over time.
In addition to age and lack of care, extreme temperatures, frequent short trips, and leaving the lights or accessories on when the engine is not running can also contribute to battery failure.
To prevent battery issues, regular maintenance and testing can help identify and address potential problems before they cause stalling or other engine issues.
#7. Overheating Engine.
Overheating is a common problem that can cause a car engine to stall or shut off unexpectedly while driving.
When the engine becomes too hot, it can damage various components, including spark plugs, sensors, and fuel systems. This can cause the engine to misfire or fail, leading to stalling or shutting off.
Overheating can occur for various reasons, such as a malfunctioning radiator, a failed water pump, or low coolant levels. To prevent overheating and engine stalling, regularly checking and maintaining the cooling system is essential.
This includes ensuring proper coolant levels and performing routine maintenance such as flushing the system and replacing old or worn-out parts.
Also, driving habits can affect engine temperature, so avoiding driving in hot weather or stop-and-go traffic for extended periods is essential.
#8. Malfunctioning Mass Airflow Sensor.
The mass airflow sensor measures the amount of air entering the engine and sends this information to the engine control unit. Based on this information, the fuel injection system adjusts the fuel-air mixture to optimize combustion and improve fuel efficiency.
However, if the mass airflow sensor malfunctions, it can cause the engine to stall or shut off unexpectedly while driving.
This is because the engine control unit will not receive accurate information about the air intake, leading to an incorrect fuel-air mixture and misfires.
A malfunctioning mass airflow sensor can have many symptoms, including stalling, hesitation, rough idling, and decreased fuel efficiency. It can also trigger the check engine light, indicating a problem with the sensor.
To prevent stalling or other issues caused by a malfunctioning mass airflow sensor, it is essential to regularly check and maintain the sensor, including cleaning or replacing it as necessary.
#9. Vacuum Leaks.
The engine’s vacuum system plays a crucial role in regulating various functions, such as controlling the air and fuel mixture, emissions, and more.
When there is a vacuum leak in the engine, it can cause a decrease in power, rough idling, and eventually lead to the engine stalling.
Various factors, such as damaged or cracked hoses, faulty intake manifold gaskets, or a malfunctioning vacuum brake booster, can cause vacuum leaks.
Signs Your Car Might Shut Off While Driving
As you can see, there are many potential reasons for stalling. In most cases, though, there will be some telltale signs before the unwanted event occurs. Recognizing these signs early can help you address potential issues before things get out of hand.
Here are some key indicators that your car is on the verge of turning off:
- Black smoke from exhaust: Black smoke may indicate excessive fuel or incomplete combustion, leading to engine problems.
- Unusual jerking noises: Jerking or sputtering noises signal issues with the ignition or fuel system.
- Dashboard warning light: Warning lights related to the engine, battery, or oil pressure can provide early indications of potential problems.
- Strong smells: Unusual smells, such as burning oil or coolant, may indicate underlying issues that could affect engine performance.
The Steps To Follow When Your Car Shuts Off While Driving
Needless to say, having your car stalling while driving might leave you stranded in the middle of nowhere, or become a safety hazard if you’re driving at high speed or on the highway.
Follow the steps below to maintain the safety of yourself as well as other vehicles on the road:
#1. Pull your car over to the side of the road.
The very first thing you need to do when your car shuts off while driving is not to panic and guide your car to the side of the road.
Pull over to prevent any vehicles behind crashing into your rear, as cars on the highway often drive at high speed. Note that your car will be losing the ability to brake and steer, but this is your only course of action.
In the case that slowing down your car is too difficult, find a safe place to stop your car, and engage the emergency brake. This will cause an abrupt stop, but it’s a hundred times better than abruptly stalling out in the middle of the road!
#2. Restart your car.
Now that your car is safe off the side of the road, check if you can restart your car so that you can at least drive to the nearest auto repair shop.
If you’re lucky and can determine or narrow down the culprit, you might in some cases be able to make your car restart.
#3. Use emergency flashers to alert other drivers.
If you can’t restart your vehicle, use emergency flashers to notify other drivers to keep you safe while figuring out the next steps.
#4. Call your emergency number or a roadside assistance service.
When a car is stuck on the road and there is no help in sight, it’s best to seek help from an emergency number or a roadside assistance service like AAA, which usually has 24/7 assistance.
Alternatively, the police can also help you contact roadside assistance if you don’t have service or your phone is dead, and they will make sure that your car is safe.
And if you’re a bit lucky, your car might shut off but starts again so that you can get home.
You can use an OBD2 scanner at the earliest opportunity to check for any trouble codes in the engine control unit. Continue the diagnostics of the trouble code if you get any.
How do we Minimize car dies while driving?
Nobody wants to get stranded in the middle of nowhere. But we often disregard some minor things that could save us from this headache.
We can minimize the chances of having our car die while driving by checking and cleaning the fuel filters regularly, ensuring our gas tank does not go less than a quarter, and replacing faulty components like the fuel pump when they start failing.
Components like fuel pumps do not fail suddenly. It usually has tale-tell signs before it fails completely. Always replace the fuel pump once it starts acting up when hot. If not, it’ll disappoint you one sunny afternoon.
How to Diagnose Your Car That Shuts Off While Driving
If the car does not shut off while driving while you’re on the road, you can diagnose the problem and fix it. Remember that it’s a bit difficult to diagnose the problem, as it can be as complicated as a dead battery or as simple as needing to top up the fuel tank.
Follow these steps to diagnose your car when it shuts off while driving.
- Check the fuel level. If unsure, you can fill the tank with four liters or one gallon of fuel and restart your car. This will also help you identify problems with the fuel level gauge.
- Use an OBD2 scanner to check for trouble codes in the engine control unit. If you get any codes, you can pinpoint the problem.
- Check your car battery with a battery charger. You should also check the battery voltage. If your car comes on after charging the battery, measure the voltage. With a 13 volts rating, the alternator system has a problem while the vehicle is running.
- Use a fuel pressure gauge to check if the engine receives the correct pressure. If the pressure is low, check your filter and pump, and replace them.
- Use your diagnostic tool to check live data of your car, and look for any strange ratings.
- Check for an RPM from the crankshaft sensor while cranking the engine.
How To Fix A Car That Shuts Off While Driving
If your car shuts off while driving, the first thing you should do to fix it is to check the engine control module for error codes and all sensor data. You also want to make sure there is fuel in the tank and that the alternator is charging.
Here is some more detailed information on how to fix your car shuts off while driving issue:
#1. Check trouble codes.
With older car models, you had to diagnose the car with a multimeter or just common sense to find a problem.
Fortunately, modern cars have built-in diagnostic software that detects when there is a problem with one of the engine sensors and then stores a fault code resulting in a check engine light.
This makes diagnosis much easier, and you don’t have to waste time measuring every sensor in your car engine. You also don’t have to guess and replace the wrong parts.
So the best way to find out why your car shuts off while driving is to check these trouble codes in the engine control module and see if there is any stored issue.
To read the fault codes, however, you need an OBD2 scanner. You can either buy one yourself, or you can go to a repair shop, and they will read the codes for you.
Continue troubleshooting with the information you received from the diagnostic scanner. For example if you find a misfire trouble code, it could be caused by bad spark plugs, the ignition coil, or the ignition system.
#2. Check The Alternator Voltage.
If you don’t have an OBD2 scanner or can’t find any stored trouble codes, the next thing you want to do is check the alternator voltage with the engine running.
Basically, you need to apply the emergency brakes and start the engine and measure the voltage of the car battery with a multimeter. If you get a reading below 12.5 volts, there may be a problem with your alternator or charging system.
#3. Fill The Fuel Tank.
While it may seem obvious that you need to fill up the fuel tank, you may actually be low on fuel even if you don’t know it. Low fuel can cause the engine to stall when cornering at higher speeds because the fuel pump will suck air instead of fuel.
There is also a risk that the fuel gauge sensor in your tank is faulty, and your fuel level is low even though your fuel gauge says it is full. So this is definitely something you want to check by opening the fuel cap and adding a little fuel.
#4. Check Fuel Pressure.
Low fuel pressure is another common issue when your car shuts off while driving, so you’ll want to check the fuel pressure in your car. The best way to check fuel pressure is to connect a manual pressure gauge to the fuel rail or line.
You can also use a diagnostic scanner to measure the pressure from the vehicle’s pressure sensor if there is one, but there is always a risk that this sensor is bad.
Check the fuel pressure specifications for your car, and if you notice that the fuel pressure is low, you need to inspect the fuel filter, fuel pump and fuel pressure regulator.
#5. Inspect The Tachometer.
The RPM meter or so-called tachometer on your dashboard receives the information from the crankshaft position sensor in most car models.
If you notice that your tachometer does not work when your car shuts off while driving, or if it does not move when you start the engine, it could mean that there is a problem with the crankshaft position sensor or camshaft position sensor.
#6. Check The Dashboard.
The next thing you want to check is the lights on your dashboard when your car shuts off. If you notice that the lights on the dashboard turn off when the car engine shuts off, this may indicate a problem with the ignition switch.
But it can also be caused by low battery voltage due to a bad alternator as we discussed earlier. If that’s the case, you definitely want to inspect both of these things.
#7. Check Sensor Data.
If you cannot find any error codes stored in the ECU, but still have a problem with your car, you need to check data from all car engine sensors with an On-Board Diagnostic Test.
To check this data, you need a diagnostic tool compatible with your car’s engine control module. It can also be quite difficult to know what readings these sensors are supposed to give, so you will first need to obtain a repair manual or the specifications of your vehicle.
#8. Talk To A Professional.
If you’ve tried everything above but your car still shuts off while driving, it may be wise to seek the help of a professional. Although it may cost a lot of money, it may be wise to get help from someone who has dealt with this issue many times before.
It’s also not certain that it will be more expensive to have a mechanic take a look at it, if he can locate the problem quickly and accurately instead of replacing the wrong parts.
How to Prevent your car from shutting off while driving?
If you want to avoid being in such a situation where your car shuts off:
- Provide regular maintenance for your car.
- Make sure to check important components like the engine regularly.
- Pay attention to any warning symbols that appear on your dashboard.
- You also need to keep in touch with your technician to direct you about the steps that need to be taken, the parts which need regular maintenance.
- And let him make a schedule for you to follow in order to keep your car running safely and efficiently.
Importance of Regular Maintenance
Regular maintenance of your vehicle is essential to ensure optimal performance and prevent potential issues.
By taking preventative measures and staying on top of your vehicle’s upkeep, you can enjoy long term benefits and avoid unexpected breakdowns. Here are five critical reasons why regular maintenance is crucial:
- Oil Changes: Regular oil changes help lubricate the engine, reducing friction and preventing wear and tear on vital components.
- Filter Replacements: Changing filters like the air filter and fuel filter ensures that your engine receives clean air and fuel, improving performance and efficiency.
- Tire Rotations: Rotating your tires regularly promotes even tread wear, extending their lifespan and enhancing safety on the road.
- Fluid Checks: Monitoring and topping up essential fluids such as coolant, brake fluid, and transmission fluid prevent overheating and component damage.
- Brake Inspections: Regular brake inspections help identify potential issues early, ensuring your brakes function correctly and guaranteeing safe stops.
Investing in regular maintenance now can save you from costly repairs and downtime in the future, making it a wise choice for any vehicle owner.
FAQs.
Q: What would cause a car to just die while driving?
As explained earlier, several factors like a bad alternator, defective fuel pump, lousy car battery, no voltage from the camshaft position sensor or malfunctioning camshaft position sensor, and other fuel system and ignition issues can cause a car to die while driving.
Q: When a car dies while driving, is it a battery or alternator?
If you have to jump-start your car every time and it keeps running, but it won’t start on its own without jump-starting it again, you have a dead battery that needs replacement.
But if the engine starts but dies immediately, you probably have a bad alternator. The only solution would be to repair or replace the alternator.
Q: What electrical problem causes the car to shut off while driving?
The car alternator is the powerhouse of all the electricity in a car. The alternator is responsible if an electrical problem causes your car to shut off while driving.
If it becomes faulty while driving, the car will run on the battery power and shut off once the battery is out of electric juice. It does not start the vehicle, but it helps recharge the battery and supply electric flow to electronic components in the vehicle.
Final Words
There are many reasons why a Car dies while driving and won’t start. Some of them will depend on the model of the car you are driving.
However, the tips given in the above guidelines apply to almost all vehicles. To avoid or reduce the chance of getting into these situations, you are required to take some precautionary actions.
It is advisable to change the fuel filter as per the manufacturer’s recommendations. You also need to have the fuel in at least a quarter tank. This will increase the life of the pump and prevent clogging of the fuel filter.
Always remember that safety comes first. If you have any vehicle failure issues on the road, always warn the cars behind you and get in the low-speed lane until you get the right help.