Wondering why does my car stall when idling or stopped? Read the blog till end to know all the major reasons behind it.
Let us imagine you are getting late for an important event. Before reaching your destination, you park your car outside a shop to buy something. You return to start the car, but you realize that the engine is not starting, and it dies suddenly. Besides the panic of getting late and disappointment because of your luck, you will probably be surprised how your car’s broken engine died just like that without any warnings.
Your engine likely stalled if it shuts off while idling. But, what results in a car stalling out? If you wonder “Why does my car stalls when idling or stopped”, it typically indicates that the engine isn’t getting enough fuel, air, or power. There are six primary causes of an automobile stalling while idling, which are as follows:
- The faulty mass airflow or oxygen sensors
- Defective transmission
- Clogged EGR valve
- Defective idle air control actuator
- Bad spark plugs
- Difficulties with the fuel delivery system
Your SUV, car, or truck stalling repeatedly indicates an issue that needs to be fixed. If you ask yourself,” why does my car stall when idling” you will find the answer in this blog.
Why Does A Car Stall While Idling?
If a car engine dies while idling, it has stalled. If you wonder “Why does my car stall when idling?”, which happens if your engine has not received enough fuel, air, or ignition-related issues.
1. Fuel: A car cannot run without power. A bad fuel pump or a clogged fuel filter, or the wrong fuel in the engine will cause the engine to die out while idling.
2. Air: To run the engine, we must produce energy by burning fuel and air. Suppose the air intake filter, which refines the air going to the combustion chamber, gets clogged with dirt, pollen, debris, etc. In that case, air won’t be able to go inside the combustion chamber, which will hamper the combustion process and stall the vehicle.
3. Ignition: Spark plugs not firing on time to begin the ignition process will also cause the car to stall. Also, if the crankshaft or the camshaft position signals are left undetected, the fuel injectors do not get the instruction to inject the fuel into the cylinders, and the spark plugs do not get the call to fire.
5 Causes Why Your Car Is Stalling
A car that stalls every time you idle is the last thing you need when you’re in traffic. What might be wrong if you’re continuously annoyed when this occurs with your car? Here is a list of possible reasons that causes your car to stall while idling:
1. The Faulty Mass Airflow Or Oxygen Sensors
The oxygen sensor and mass airflow sensor are present in cars that monitor the inflow and outflow of air. Even if one of the sensors gets worn out or damaged, the amount of air it sends inside the combustion chamber is altered, which changes the ideal ratio of air and fuel in the air-fuel mixture. This causes trouble in fuel combustion, leading to stalling.
2. Defective Transmission
In automatic cars, the torque converter functions as the automatic clutch; it is responsible for channeling power from the engine to the whole drivetrain in automatic transmissions. A failing torque converter causes stalling of the car and needs extensive repairs, which are heavy on the pocket. Fortunately, if you are lucky enough, the malfunction in the transmission is caused by a defective solenoid, which helps regulate pressure. It is simple and inexpensive to fix a broken solenoid.
3. Clogged EGR Valve
EGR stands for Exhaust Gas Recirculation. EGR’s function is to recirculate some exhaust back to the combustion chamber. It is to maintain an optimum temperature inside the engine. As they primarily composed the exhaust gas of carbon dioxide, it does not burn inside the combustion chamber, effectively lowering the temperature.
When the valve controlling the inflow of EGR gets clogged, it remains open or closed, which causes the exhaust to flow continuously or stop flowing. As this happens, the ratio of air/fuel inside the combustion chamber changes and causes a loss of power.
4. Faulty Spark Plugs
Spark plugs are the component that ignites the air/fuel mixture at the combustion chambers, which powers the car’s engine to make it run. If the spark plugs wear out, it becomes less effective at igniting the mixture, leading to less power being delivered to the engine and getting it stalled.
Following are the common types of plugs available in the market, which are Copper, Platinum (Single and double), Indium and Silver. Depending upon the type, the spark plugs last between 10,000 to 100,000 miles. Copper spark plugs are the cheapest and last the shortest (10,000 to 20,000 miles). Silver, platinum, and Indium spark plugs are more costly and last about 100,000 miles.
5. Difficulties With The Fuel Delivery System
The fuel delivery system, including the fuel pump, is responsible for delivering fuel from the gas tank to the engine. A good fuel pump will need to provide energy effectively to the combustion chamber. This problem becomes one of the most common reasons your car stops when stalled and goes uphill/downhill.
Another component is fuel filters, which, as its name suggests, filter harmful debris before it can reach the engine. If the fuel filter gets clogged, it is challenging to send sufficient fuel to the combustion chamber, which will cause improper combustion and less power being delivered to the engine, thus causing the car to get stalled. If you ever wondered “Why is my engine stalling?”, issues in the fuel delivery system can be a reason.
1. How do I fix an engine stall?
When you face a stalled engine, the first thing you have to do is not panic. Then you can analyze which part is causing your engine to stall while idling and fix the problem.
- Mass Airflow Sensors: When checking for mass airflow sensors, ensure there isn’t any leakage between the sensor and the throttle body. Also, check if there is dirt accumulated on the sensor body; if there is dirt, clean it using MAF (mass airflow sensors).
- Faulty EGR: A faulty EGR will result in the accumulation of carbon buildup around the valve, which opens the valve for a prolonged time. If EGR is faulty, you will experience a rough idle while stopping the car, increased fuel consumption, odour, etc. To repair the stalled car, you have to examine the valve and remove the carbon buildup around it.
- Bad Spark Plugs: If your car gets stalled and experiences the engine producing rough noises while cruising idle or your engine surges or misfires and cannot make acceleration, it means the spark plugs have worn out, and to repair your stalled car, you need to replace them.
Although you can analyze the problems from manuals or the web and repair the faulty parts yourself at home, the car inside is complex and has numerous small factors. It is better to take the vehicle to a repair shop and let the experienced mechanic handle the problem.
2. What sensors can cause stalling?
Having faulty air oxygen sensors or mass airflow sensors can cause stalling. These sensors monitor and control the amount of air in the combustion chamber, and if either becomes defective, the ideal air/fuel ratio for combustion gets hampered. If the discharge is not adequate, the power supplied to the engine is less, and thus your car will get stalled.
3. Can bad spark plugs cause stalling?
Spark plugs play a critical role in starting the engine as it is used for ignition, which creates the combustion process. If your spark plug is worn-out, the efficiency with which your spark plug will ignite the mixture will also be inferior, resulting in lesser power delivered to the engine and hence causing stalling.
A stall, which is defined as the slowing down or stopping of a process, occurs when an engine suddenly stops turning. It might occur as a result of a lack of fuel, energy, air, or electric spark, fuel deprivation, a malfunction, or an unexpected rise in engine load.
So, if you still wonder “Why is my engine stalling?”, you would know by now. Stalling the car while idling is rare, but it happens now and then when it happens try to diagnose the problem by yourself or find the best auto repair shop and get the defect fixed by professionals as soon as possible.