Picture this: you’re sitting in your automobile about to shift out of Park when the engine suddenly stalls.
There were no cautionary signs, no indicator lights, and everything seemed fine. It just shut off.
Why does an automobile cease functioning while idling in Park?
When your engine dies while idling, there’s a good chance that it stalled. What causes a car to stall out? Generally, it means the engine isn’t receiving sufficient air, power, or fuel.
There are six primary reasons that might cause a car to stall while idling. The main reasons are:
- Faulty oxygen or mass airflow sensor
- Clogged EGR valve
- Bad spark plugs
- Idle air control actuator problem
- Fuel delivery system issues
- Malfunctioning transmission
If your SUV, car, or truck keeps stalling, it suggests that there is a problem that needs to be taken care of.
Thankfully, in this guide, I will examine each of these in detail so that you know how to proceed.
Let’s plunge right into the guide!
Table of ContentsShow
6 Common Causes Of A Car Stalling At Idle
Faulty Oxygen or Mass Airflow Sensor
Your vehicle is filled with numerous sensors. Each relays specific information to the ECM (Engine Control Module). The ECM then takes this data and regulates how the engine operates to ensure it’s running optimally.
Two of these sensors play a vital role in why a car engine stops while idling. The first is the oxygen sensor located in the exhaust manifold.
The second is the mass airflow sensor, which sits to the left of your engine inside the intake air passage.
The preceding reads the quantity of air leaving your engine, and the latter measures the volume entering. The ECM uses this information to increase or decrease how much air it sends to the combustion chambers.
If either of these sensors is transmitting erroneous information, then your engine might not receive sufficient air, which it needs to power itself. A lack of air leads to a lack of power, which can cause your car to stall while idling.
How much does replacing an oxygen or mass airflow sensor at a shop cost? An oxygen sensor will run about $200, and a mass airflow sensor will cost roughly $300.
Clogged EGR Valve
If you didn’t know, EGR stands for Exhaust Gas Recirculation. As its name suggests, its purpose is to recirculate a tiny amount of exhaust back into the combustion chambers. It does this to reduce the temperature inside.
This works because exhaust gas is mostly carbon dioxide (C02), which is an undetectable, colorless gas that doesn’t burn.
Since it doesn’t burn like oxygen, it effectively lowers the temperature inside the combustion chambers.
When the EGR valve gets obstructed, it may get stuck open or closed, meaning exhaust gas will continue to stream or not flow at all.
When this occurs, it impacts the air/fuel ratios inside the combustion chambers, which can lead to a loss of power. Not sufficient power, and you’ll have stalling problems while idling.
Diagnosing a clogged EGR valve, though, is a bit more intricate because a lot of the symptoms are comparable to those caused by a defective fuel pump, clogged fuel filter, or bad spark plugs.
Fortunately, if it is a blocked EGR valve, you can simply clean it out at home rather than replace it for $400-$500.
New Spark Plugs Needed
Spark plugs are in charge of igniting the air/fuel mixture inside the combustion chamber. As you might expect, if they’re aged and worn, they’re less efficient at doing their job. This translates to less power for your engine, which can lead to your car stalling at idle.
There are five classifications of spark plugs on the market today. These consist of the following:
- Copper
- Iridium
- Single Platinum
- Double Platinum
- Silver
While copper costs the least, they only persist for between 10,000-20,000 miles.
Iridium, silver, and both single and double platinum all persist for roughly 100,000 miles but have steeper prices.
Defective Idle Air Control Actuator
The purpose of the idle air control actuator is to keep the RPMs in an optimal range while the engine is idling. It does this based on input received by the ECM, which it gets from things like your mass airflow, oxygen, and fuel sensors.
If there’s an issue with the idle air control actuator, the rotational speed of your engine might fall too low.
As you might have surmised, this can cause your engine to stall while idling.
The cost to replace this part varies significantly. It ranges from just over $100 to as much as $500, including both parts and labor.
Fuel Delivery System Issues
As we mentioned earlier, three main elements usually lead to a car stalling out while idling. One of these is a lack of fuel, meaning a problem in your fuel delivery system can result in your car dying.
Any component of the fuel delivery system can cause this. Take the fuel pump, for instance, which is accountable for delivering fuel to your engine from the gas tank.
Additionally, there is the fuel filter, which filters detrimental debris before it reaches your engine. If it gets clogged, insufficient fuel will reach the combustion chamber.
If you’re fortunate, it’s just the fuel filter, which typically costs between $50-$150 to replace. Most last for about 2-years, so if you’re long past this, it’s likely the issue.
Malfunctioning Transmission
Just mentioning a transmission problem is likely to send chills down the spine of any car owner.
Why?
Because they’re tremendously costly to work on.
As far as engine stalling problems, we’re specifically talking about the torque converter, which is essentially the automatic counterpart of a clutch.
Its purpose is to deliver power from the engine to the rest of the drivetrain. If it’s worn or impaired, it’s unable to do this efficiently, which can cause your car to stall.
Thankfully, it may just be the solenoid, an electromagnetic component that gauges and regulates fluid pressure. If this is found to be the issue, you’re only looking at a repair cost of around a few hundred dollars.
Don’t Remain Idle If Your Engine Stalls While Idling
Ignoring a vehicle that keeps stalling will only lead to more serious issues.
Rather than sitting around and hoping that it fixes itself, take action instead. That’s simply because when an engine dies at idle, something is awry that needs your attention swiftly.