Why Does Car Turns Off While Driving But Turns Back On?

When you own a car, it is your responsibility to care for it. Many car owners seem to think a car runs on magic dust. You have to continually check oil, gas, coolant, etc., to make sure your car stays fit for a long time. In modern vehicles, there are many sensors and functions to make your car run smoothly. Having basic knowledge about your vehicle can help you counter a mechanical problem like your car shutting off while driving.

If your car turns off while driving but turns back on suddenly, it can often be due to a bad fuel pump. Your engine needs a precise supply of fuel at a precise time as input for combustion to generate power, and the fuel pump is the part that supplies the engine with the correct amount of fuel. In this article, we’ll shed on the reasons for this issue so the next time it happens; you are well-prepared. 

Why Does Car Turns Off While Driving But Turns Back On?

The most common reason a car shuts off while driving is due to a bad crankshaft position sensor or issues with the fuel system. It can also happen due to a bad alternator, ignition switch, empty fuel tank, or car engine sensors problems.

1. Faulty Crankshaft Position Sensor:-

The most common reason a car shuts off while driving is a defective crankshaft position sensor. The crankshaft sensor is necessary for your car engine to run on most car models. You also have a camshaft position sensor on some car models, which the car uses if the camshaft sensor is faulty. Here, a faulty crankshaft position sensor may not cause the vehicle to stop entirely. However, if your car is equipped with a crankshaft position sensor but not a camshaft sensor and you get a trouble code on it, you need to replace it.

2. Faulty Fuel Pump:-

A fuel pump supplies the engine with the correct amount of fuel. If the fuel pump does not provide the right fuel to the engine, the motor will shut off, and you will be left stranded. A fuel filter is a small component whose only job is to clean the fuel that goes into the engine. If the fuel filter is clogged, the fuel entering the system will be insufficient, and the engine will shut down. Fortunately, it is easy for you to replace a fuel filter. If your car turns off while driving but turns back on suddenly, it can often be due to a bad fuel pump.

3. Empty Fuel Tank:-

If you have sufficient fuel for your drive, that is perfect, but if your fuel gauge or fuel level sender has gone faulty and does not show the real fuel level in your car, you could have a big problem. An easy way to try if there is a problem with your fuel gauge or fuel level sensor is to fill 1 gallon (4 liters) of fuel to see if it starts.

4. Alternator Problems:-

An alternator manages the supply of electricity in your vehicle. If your car suddenly stops running, the alternator may have gone bad. A faulty alternator will cut the power supply to vital car components, and you will notice the lights turning off in the dash or the engine abruptly losing power.

5. Faulty Ignition Switch:-

Sometimes, a faulty ignition switch can cause your car to shut off while driving. The ignition switch is installed behind the ignition lock and get’s turned while you turn the key to start the car. Inside this switch, tiny metal plates can build up corrosion and rust. If this happens, one of these plates may lose connection, and the whole ignition will get switched off. This will also cause the whole engine to shut off immediately.

6. Malfunctioning Sensors:-

Modern cars have many sensors to optimize the air-fuel mixture for optimal fuel consumption. If one sensor fails and is off, your car engine might die altogether. Sensors like the MAF sensor, Coolant temp sensor, and Oxygen sensor could mess with the air-fuel mixture so much that the engine would die.

How To Diagnose A Car That Shuts Off While Driving?

Diagnosing a car that shuts off while driving can be difficult if the problem comes occasionally. However, it is much easier to find the problem for a car that just died after driving.

Step 1:-

Check for any trouble codes in the engine control unit with an OBD2 scanner. Continue the diagnostics of the trouble code if you get any.

Step 2:-

Fill the tank with 1 Gallon or 4 liters of fuel to ensure the fuel level is good, and there is nothing wrong with the fuel level gauge.

Step 3:-

Check the battery voltage and connect a car battery charger to make sure the battery charge is good.

Step 4:-

If you can start your car after the charging of the car battery. Measure the voltage with a multimeter while the car is running. If it is 13.5-14.5 voltage, your alternator is fine, but if you get under 13 volts while the car is running, there is something wrong with the alternator system.

Step 5:-

Check if the engine has correct fuel pressure with a fuel pressure gauge. If not – check the fuel pump and fuel filter. Replace if faulty.

Step 6:-

Check live data with your diagnostic tool and look for any strange values from the engine sensors. Check if you get RPM from the crankshaft sensor when cranking the engine.

Step 7:-

Check the RPM meter on your dashboard while cranking the engine on the starter motor. If it doesn’t move – the problem is most likely the crankshaft position sensor.

Therefore, these are some diagnosing steps for the problem car turns off while driving but turns back on suddenly.

FAQs:-

1. Can low oil cause a car to shut off?

Low engine oil levels do usually not cause your car to shut off. However, if it is so low that your oil pressure is getting low – the car can shut off the engine for safety reasons. This is often in newer cars, though.

2. Can a bad battery cause a car to shut off while driving?

A bad car battery rarely causes the engine to shut off because the alternator gives the required power it needs. It can be such a short circuit in the car battery in some rare cases, so it will shut off, though.

3. Why does my car keep cutting off when I stop?

If your car shuts off after you stop, the engine is very sensitive at idle. This can be caused by many things but is usually caused by a lean fuel mixture, causing the idle to drop too low. A faulty throttle body can also cause this.

4. Why did my car shut off while driving and won’t start?

If your car shut off while driving and it won’t start, it is often caused by a faulty alternator or low fuel pressure caused by the fuel pump. However, many things can cause it, and it needs to be diagnosed with a diagnostic scanner.

Conclusion:-

We hope the above-mentioned information about the car turns off while driving but turns back on suddenly will be helpful to all the readers. If anybody’s doubts persist feel free to comment in the comment section below. We’ll definitely try to solve your doubts as soon as possible.

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