Top 8 Causes of Cars Shutting Off While Idling (And What To Do About It)

Car Shuts Off While Idling

Like other mechanical structures, cars also have issues affecting their performance. One problem is when a car shuts off while idling.

Even though your car is designed to run smoothly, it can sometimes malfunction, and this can happen even while you're driving at a steady speed.

Now, there are various reasons why your vehicle will shut down while idling. Let’s look at them in this article and also offer practical solutions to them.

Before you start to worry, make sure that you have a mechanic inspect your vehicle.

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Reasons Car Shuts Off While Idling Video

Why Your Car Shuts Off While Idling

It can be very frustrating to have your car suddenly stop working while driving at low speeds or idle.

Unfortunately, this issue can also occur while you're running late for work or on a busy street.

Although there's never a convenient time for your car to shut off while idling, some situations can be hazardous and inconvenient.

There are several reasons your car shuts off while idling, and it can be hard to identify the exact cause of this issue.

For instance, if you accidentally operate the clutch incorrectly, it might cause the gears to disengage and cause the engine to stop working.

Since automatic transmissions don't have a manual clutch, this issue is more likely to be mechanical.

When the engine stops working, it's not getting enough fuel, air, and power. These are the reasons why your car shuts off while idling;

1. Not Enough Air

The airflow in and around your car's engine is crucial to its operation. If there's a lack of oxygen, it can affect the efficiency of the engine.

Poor airflow can cause the car to stall. Aside from the engine components, other factors can also affect the airflow in your vehicle.

2. Faulty Oxygen Sensor

The car's oxygen sensor measures the oxygen level in the exhaust as it leaves the engine.

It then passes this information to the control unit, which then regulates the amount of air that's going into the car's engine. If the sensor is not working correctly, it can cause the engine to stop working.

A new oxygen sensor can cost around $100, though the exact cost depends on the make and model of your car. It can take around an hour to install.

3. Mass Air Flow Sensor Problems

A different type of sensor, the mass air flow sensor, is also used to measure the airflow in and around the engine.

However, it doesn't monitor the oxygen levels from the exhaust; it only monitors the oxygen going in. In the case of inaccurate readings, this can cause the control unit to malfunction.

Depending on the make and model of your car, the cost of a new mass air flow sensor can range from $50 to $400.

However, its installation is relatively easy and typically adds no more than $50 in labor costs.

4. Clogged Exhaust Gas Recirculation Valve

This component is commonly found in diesel engines, though it can also be found in newer gasoline models.

When the engine runs, the exhaust gas recirculation valve allows small amounts of exhaust to flow back into the system to cool the engine. Since carbon dioxide doesn't burn, this process helps the engine run smoothly and safely.

Unfortunately, over time, debris can get stuck in the exhaust's stream, clogging the valve.

This can prevent it from regulating exhaust flow through the engine, which can cause the car to stall.

Getting the car's exhaust gas recirculation valve fixed can be as simple as washing it out at home. However, if the valve is faulty, replacing it can cost around $500.

5. Lack of Fuel

When your car stops working while you're driving, your first thought might be that there's something wrong with the fuel delivery system of your vehicle. This is because if there's a problem with the fuel supply, it could cause the engine to stall.

The fuel delivery system of your car is composed of various components, such as pumps, sensors, and filters.

Since a lack of fuel can cause your car to stop working, you must regularly inspect your vehicle's fuel delivery system. This component should be checked to make sure that it's working correctly.

6. Insufficient Power

Aside from the engine, other components also play a vital role in keeping your car running.

7. Spark Plugs

An essential component of your vehicle is a spark plug, which is the part of the ignition system that ignites the combustion process.

When the fuel injectors are pushed into the chamber, the spark plugs light up the gas, producing the combustion reaction. Unfortunately, over time, these components can wear out and become damaged.

You'll typically pay around $85 for a new spark plug, and you'll also have to spend about $150 for labor. However, replacing these components is relatively simple, and it can be done on your own.

This process can save you a lot of money in the long run, especially if you have a used car with copper spark plugs.

Although they're less expensive than other spark plugs, the silver, platinum, and iridium ones typically last about 30,000 miles. On the other hand, the long-lasting models can last up to 100,000 miles.

8. Transmission

Getting scared away by the cost of repairs is usually the reaction of most drivers regarding transmission problems.

However, when it comes to car stops, the issue is likely not the transmission itself but the other related components.

One of the essential components of your car is a power-to-wheel drive system composed of a transmission and a set of components known as the torque converter.

If the system is not working correctly, it could cause your car to stop working.

Since your technician will have to remove and replace the transmission, it usually costs around $1,000 to replace the converter.

This process can be very complex and challenging, so unless you have a lot of car experience, it's best to leave it to the professionals.

What To Do if My Car Shuts Off While Idling?

Before you start addressing the issue, make sure you're taking the necessary steps to ensure that it's safe for you and your vehicle. For example, if the engine still doesn't start, you might need to have it towed.

You might need to contact a professional mobile mechanic if the issue persists.

This individual will come to your home or work to determine the cause of the problem and develop a detailed inspection report.

After testing your car, the mechanic might also need to listen to the engine to identify any unusual noises or misses.

The mechanic will then use a scan tool to look for stored codes. The scan tool will allow the mechanic to access the transmission control computer and the control unit.

After testing the car, the mechanic will determine the cause of the issue and come up with a diagnosis.

They will also need to identify the various components that need to be replaced or cleaned. This process can take a long time since multiple items could be involved.

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Address the Problem Right Away

Some of the most common reasons your car will stop working while idle are not the engine itself but the other components.

If these aren't the cause of the issue, the mechanic can help identify the other possible reasons.

Regardless of the reason for the issue, you must take immediate action to address the issue to prevent it from happening in the future.

This is a severe problem that can affect your car's performance and could cause further damage.

Regular tune-ups can also help identify potential problems early on, which can help prevent them from happening in the future.

When To Avoid Idling

It's essential to reduce your vehicle's idling time as much as possible to avoid further pollution and save gas. However, there's one place you should never let it idle: at the gas pump.

While filling up your tank, the engine fumes from your car's engine can cause an explosion or a fire. Since the engine's heat can still reach dangerous levels, it's essential that you immediately shut off the car when you're at the pump.

Is Idling Bad for My Car?

Although it's okay to keep your car running while idle, prolonged use of this practice can cause the issue.

Generally, you should not let your car idle for more than 30 seconds at a time while driving.

However, if you're waiting for a friend to arrive in a parking lot, you might leave your car running for up to 15 minutes but not frequently.

In addition to damaging the engine, prolonged use of idle can also contribute to air pollution. Turning off the engine and opening the windows to breathe fresh air is essential.