Whenever the unfortunate incident occurs, a stalled car engine can quickly become a stressful endeavor. It can be even more distressing if the engine stalls while you’re driving because it is not only an extreme safety hazard, but it can also end up leaving you stranded on the side of the road.
If your engine is stalling, you need to address the situation as soon as possible. The first step is knowing and understanding the causes of a stalled engine.
There are several reasons why your motor may stall, and this guide will explain in detail some of the most common causes.
Your Battery Has Failed
We’ve all had that feeling at some point or another. That sinking feeling of getting ready for work in the morning, only to discover that your car won’t start. But what many people don’t realize is that your battery continues to work hard long after the engine starts.
If the charge drops too low, the spark plugs will fail to fire, and your cylinders will fail to ignite. If your cylinders aren’t properly igniting, your engine may stall. And yes, this can even occur as you are roaring down the highway. It can happen if the battery’s cells are still fully charged. Dirty or corroded contacts can even cause it.
Thankfully, a battery is easy to diagnose. You can identify corrosion and dirt with a simple visual inspection. You can test the charge with a multimeter, an affordable tool available at nearly any hardware store. And If you don’t know how to use one, don’t worry. Any certified mechanic will surely have one on hand and can test your battery for you, many times free of charge!
Your Air Filter Is Clogged
Proper engine function requires an appropriate fuel-air mixture inside the cylinder. Too little fuel and combustion will be weak, not providing enough force. Too little air and there isn’t enough oxygen for full combustion, which will foul your engine. Continue restricting the airflow, and the engine stops running altogether.
An air filter is designed to keep dirt and debris out of your engine. However, like all things on the road, it will eventually get dirty. If you’re following your manufacturer’s recommendations on regular filter changes, you shouldn’t normally have a problem.
That said, extreme environmental conditions can clog your air filter prematurely, a common issue in areas with frequent wildfires. Smoke particles can rapidly clog your filter, which can at times cause engine stalling. If you’re dealing with unusually poor air quality, it’s best practice to have a mechanic check your filter frequently to ensure it is clean and in proper working order.
Your Timing Belt Is Worn Out
Most internal combustion engines use a timing belt or timing chain to synchronize the motor’s operation. Like other automobile components, timing belts and chains don’t last forever, and they eventually wear out and need to be replaced.
A bad belt or chain can cause stalling because they can skip one or more teeth during rotation. This desynchronizes different parts of the engine and causes irregularities in operation, often causing the vehicle to seize.
A bad timing belt is a cause for concern for other reasons, as well. When an engine seizes, the physical shock can severely damage the camshaft and other expensive parts of your vehicle.
There’s An Electrical Problem
There aren’t many electrical systems in older engines, which means that there are a limited number of potential failure points. To see if you perhaps have an electrical issue, start by checking your spark plug wires and distributor, or see if the wiring harness is shorted out to the frame.
Damaged or corroded wiring can be a possible cause of trouble in modern vehicles as well. Many newer cars are packed with all kinds of electrical components that control numerous motor functions.
One example is the Transmission Control Module (TCM). The TCM is a computer on an automatic transmission vehicle that determines when to shift from one gear to another. If the TCM shifts into too high or too low of a gear, it can cause the engine to stall. This is analogous to stalling out a manual transmission vehicle by trying to start in third gear.
Your Engine Isn’t Getting Fuel
Earlier, we addressed what happens if your engine doesn’t receive a sufficient air supply. As you might expect, a similar phenomenon occurs when there’s not enough fuel getting into the cylinders.
In this instance, the most common point of failure is the fuel pump, which is responsible for transporting fuel from your gas tank to the motor. If the pump fails, nothing happens when you press the gas pedal.
There can be other potential causes for a fuel shortage, as well. For example, the fuel line may have sprung a leak, or the fuel filter may be clogged. Unless you’re a reasonably confident home mechanic, you’ll want to have these issues checked out by a qualified professional as soon as possible.
One last possible issue could be over-fueling. In the case of over-fueling, the fuel injectors are pushing too much gas into the cylinders. A clogged air filter usually causes this problem because a lack of oxygen fails to produce full combustion.
Your Torque Converter Has Failed
Automatic transmission vehicles need to manage their level and pressure of transmission fluid when the car is idling. They do this with a component called a torque converter. When this converter fails, your engine will stall.
There are several potential causes of torque converter failure. It may have been damaged by overheating or by dirty automatic transmission fluid. They can also be damaged if the engine’s computers fail and attempt to engage the transmission at too low or too high an RPM level. This RPM level is known as the engine’s “stall speed” and can be tested by any certified mechanic.
You Need To Work On Your Technique
If you’re driving a manual transmission vehicle, it’s crucial to operate your clutch and shift gears appropriately. If you’re applying too little clutch or releasing too quickly, it can cause your engine to stall. Work on your technique and adapt it to your specific vehicle so that you can shift gears fluidly.
Summary
Your car can stall for a wide variety of reasons, but regardless of the cause, it’s essential to have the issue diagnosed as soon as possible (unless you are merely shifting gears incorrectly). Your safety, and your sanity, will benefit greatly. For more helpful tips, read our other posts!
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