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Car Starts Then Stops – Causes & Information

In Driving by Magnus Sellén2 Comments

car engine starts then stops

It can be frustrating to drive your car for miles on the highway just to have the car lose power and come to a standstill.

An understanding of how the engine works will reveal possible solutions. Your car needs fuel, coolant, engine oil, and electricity to run.

If these become unavailable, the car may come to a standstill.

Reasons your car engine starts then stops

There are some obvious reasons that you need to rule out first:

Lack of Fuel

Your car needs fuel to run. Your fuel gauge should give a warning when the fuel level is low, but there are moments when the gauge is faulty. In this case, you may assume that you have fuel when there is none. In extremely cold weather, the fuel system can freeze, which means that the fuel will not get to where it is needed.

In other cases the car may stop due to a leak in the fuel pump. The combustion unit requires a certain amount of fuel to keep the car moving. A fuel leak means that not enough fuel enters the combustion chamber. It is extremely dangerous to drive with a leaking fuel pump.

Anti-Theft Alarm System

Car alarms can be simple or complex. There are some alarm systems that switch off the engine power and prevent the vehicle from driving if an unauthorized person enters the vehicle. You may need to remove and disconnect the alarm system. Some alarm systems come with manuals to help you learn how to reset the alarm.

Dirty Fuel Filter

If the car stops after turning on the ignition, the problem could be a clogged fuel filter. The problems are not serious and you can use a carburetor cleaner to clean the fuel filter system. First, disconnect the air filter outlet, and when the ignition system returns to the operating position, spray some of the carburetor aerosol through the throttle body.

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If this does not work, replace the fuel filter and check the fuel pump, fuel pressure regulator, and ballast tank.

Faulty Spark Plugs

The combustion engine works by igniting an air-fuel mixture. The spark for this ignition is provided by the spark plugs. The pistons move up and down, which leads to movements in the crankshaft and the wheel axles. If the spark plugs are faulty, the ignition will fail and the car will stop moving. A defective camshaft sensor, crankshaft, rotor, camshaft sensor, or ECU can also affect the efficient operation of the spark plugs.

Alternator Problems

The car uses both the battery and the alternator to keep moving. These two supply most of the car’s electrical components. The battery is needed to power the stator that drives the engine. The alternator then takes over and keeps the car moving. If your alternator doesn’t work, the car may come to a standstill.

Engine Control Unit (ECU)

engine control unitThe ECU is a computer system that controls various engine functions including the fuel injection system. Since a vehicle needs fuel to move, any malfunction of the ECU will cause the vehicle to come to a halt after starting. The ECU controls the engine components via a series of sensors. Over time, the sensors become faulty and pass on erroneous information to the ECU. In this case, you must take your car to a car repair shop.

Fuel Injector

Closely related to the ECU is the fuel injection sensor. The fuel is injected under high pressure into the combustion chamber. A sensor is connected to the fuel injection system which constantly sends information to the ECU. The ECU accordingly regulates the fuel pressure depending on the information coming from the sensor. If the sensor malfunctions, the vehicle engine will fail after starting.

Faulty Ignition Switch

If your ignition switch is damaged, you may start the car normally and after a few miles the car will come to a complete stop. You will notice a loss of power before the car stops. If your ignition switch is defective, you must check the switch contacts for wear. Your mechanic can help you with this.

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Other areas that need to be checked are the throttle bodies. After repeated use, the throttle valve starts to fail due to carbon deposits. You can use the carburetor cleaner to remove the carbon deposits.

If you have ignition problems, open the engine and check each spark plug. What you are looking for is the spark gap. A good spark plug will have a grayish color. If the plugs are wet, this means that too much fuel is entering the combustion chamber and this will interfere with the ignition.

You must also check the function of the positive crankcase ventilation (PVC). This system is crucial for regulating the blowby gases from the engine to the intake manifold. If the valve is faulty, too much air will enter the intake manifold, causing the car to lock up.

Finally, you must check the exhaust gas recirculation (EGR) systems. The EGR helps to reduce the engine temperature by re-introducing the exhaust gases. Soot deposits can block the EGR valves and cause the vehicle to lock up. It can also have leaks that cause problems during acceleration. You can remove the EGR unit and check for leaks; carbon deposits can be removed with a carburetor cleaner.


It can be frightening if your car stops in the middle of the drive. This can be caused by various malfunctions of engine parts. The first part is to eliminate the obvious causes such as low fuel, faulty alarm system, leaking fuel pumps and damaged radiators.

Then you must check the ignition system, as the contact points could be worn. The fuel injection sensors could be worn, which could result in too little fuel entering the combustion chambers.

Hello I'm Magnus, the owner and the writer of this website. I have been working with cars since I was 16 and I'm specialized with in-depth Automotive diagnostics. Also been driving drifting for the last 6 years. I'm here to give you answers to all your automotive questions and I hope that you enjoy our content.

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2 thoughts on “ Car Starts Then Stops – Causes & Information ”

  1. Hello magnus please could you help me my car has just suddenly started cutting off and getting hardly any power sometimes it wont go up past 3000rpm then it will be ok after i dont understand but only yesterday it cut off while driving then started ok again but again cut off when i raved the engine and cut off altogether then after that was ok again iam lost as to what this mate could you please give me some info mate as to what this could possibly be magnus thank you

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