There’s no sign that your car shuts off when stopped or slowing down, but it can be a headache and problematic when it happens more often.
The engine suddenly turns off while operating in an unwanted situation, sometimes putting you in danger.
The article will present possible reasons and how to fix them to get your vehicle back to normal. Let’s get started!
What Are The Reasons For Car Shuts Off When Stopped Or Slowing Down
When your car shuts off when stopped or slowing down, the first reason you should think of is a failing idle air control valve.
The valve regulates the air intake to mix with the fuel. Other causes can be the problem of the transmission, injector, ignition wires, oxygen sensor, etc.
Malfunctioning Idle Air Control Valve
My car cuts off when I stop. What happened? The idle air control valve monitors the amount of air that should be taken in before the fuel-air mixture is delivered to the engine.
The valve also regulates the engine RPMs by collecting data from the ECU (electronic control unit) and identifying the RPM level.
The RPM grows during acceleration and decreases slowly to reach the normal idling speed during deceleration.
When the valve is broken, there’s no signal sent to the engine to stay in idling mode, causing a sudden shut-off.
You need to change your faulty or dirty valve to ensure the situation will not happen again. Go to the repair shop and have the issue solved.
Faulty Transmission
The torque converter in your automatic transmission, which works as a manual clutch, is in charge of sending power to operate the vehicle.
If this part is broken, your engine will struggle to maintain power when slowing down. The same scenario can happen when there’s a low fluid level or a broken torque converter solenoid (TCS).
To address the issue in this case, look for the fastest way to replace your damaged torque converter.
Putting things off will not only lead to the car cutting off when stopping but also friction, overheating, and quick deterioration of transmission fluid.
Remember to have the contaminated fluid changed as well.
Clogged Or Restricted EGR Valve
Sputter, stall, or improperly idle vehicles can be due to the blocked EGR valve.
When you don’t keep it clean, dirt can gather in the valve, leading to the broken component, and the car shuts off while stopped.
If carbon deposits obstruct the EGR, check them carefully. Spray the EGR valve cleaners and use a pipe cleaning brush to clean to liquidate the carbon accumulation.
Then, wipe the surface with a soft reg. Putting the valve in the cleaning solution is allowable when it is difficult to wash away the dirt.
Faulty Spark Plugs
Small spark plugs are another vital component in the generating-power system of your vehicle.
They ignite the mixture of fuel and air; thus, combustion happens. Every cylinder has its own spark plugs, and they’re all independent.
Therefore, your automobile is possible to move with one worn detail. Sometimes, you can still drive your vehicle with more than one broken part, but not for a long time.
If you wonder why my car turned off when I stopped, it’s because there were several faulty spark plugs.
Wiring Issue
Everybody knows that the ignition system works to ignite the combination of air and fuel to start the vehicle. Any ignition failure can create an inconsistent circuit supply to the engine.
In turn, the engine loses voltage and struggles to perform, leading to the car dying when slowing down. The wiring issue is also why your car won’t start right after turning off.
Relocate the wire when you see it’s loose, and depending on the level of broken and corrosion, you need to repair or replace the component.
After fixing, there should be enough electricity to make a spark to ignite the fuel and troubleshoot your problem.
Lack Of Fuel Pressure Or Bad Fuel Pump
The problem with my car shuts off when I stop can be the fuel system. The symptoms include low fuel pressure, bad fuel injector, and faulty fuel pump.
The engine gets the fuel from the fuel pump. Anything wrong with the pump reduces the fuel pressure and increases the chance of intermittent power delivery, and the car engine turns off when stopped.
When traveling at high speed, you may not notice any red flags. However, when you press the brake or pull over, the erratic fuel stream is the cause of the engine switching off.
A damaged fuel pump is usually accompanied by a whining noise from the tank or difficulty starting the vehicle.
In addition, since the fuel injector sprays a sufficient amount of fuel to start the engine, a bad injector can mean inconsistent spray or no spray.
Thus, it’s unavoidable to have a car cut off while stopped. If the injector is clogged, mix a cleaner with water to unclog it.
Oxygen Sensor Problem
The proper air-to-fuel ratio guarantees your vehicle runs smoothly at low speed.
The oxygen sensors or mass flow sensors play an important role in measuring the correct amount of oxygen coming to the fuel stream, so your vehicle can have the exact ratio to keep operating when slowing down.
Similar to the case where there’s not enough fuel pressure, you can not feel faulty oxygen sensors at a fast pace until you try to pull over.
You need the oxygen sensor code charts to determine the error codes and see whether there’s too much or too little oxygen or something else.
Have a qualified mechanic replace the oxygen or oxygen sensor if it’s the cause of the car shuts off when stopped. Trying to reset the mass air flow sensor can be a solution when the engine stalls.
What To Do When Your Car Shuts Off When Stopped Or Slowing Down?
The car turns off when I stop. What to do? If it’s your question, keep reading our useful suggestions below.
Pull Over
When my car cuts off when I stop, what should I do? The first thing to do when facing such a situation is to keep calm and try to pull the vehicle over to the side of the road. Panic doesn’t solve anything.
Drive your automobile to a safe place so that other vehicles running at high speed on the highway will not crash your back.
Supposing that you struggle to slow down your vehicle, you should use the emergency brake. Find a safe and empty spot to do so because an abrupt stop can happen.
Though it’s not an ideal solution, it’s still worth doing if you don’t want your engine power off in the middle of the road.
Try To Restart
The next step you should do after pulling over is to try to restart your car to identify whether the engine can operate again.
Sometimes, luck is on your side when you can diagnose the cause or at least restart the car successfully to drive it to the nearest repair shop.
Examine The Fuel And Electrical System
Why do my car cut off when I stop? Lack of electrical charge or gas for igniting can be the root of the problem.
In this case, there’s no chance for the engine to transform the fuel. Therefore, check the fuel and electrical system to point out the real issue.
Adjust The Injector Or The Distributor Timing
While staying safe on the side of the road and examining the possible cause, don’t forget to use the proper tools to adjust the distributor timing.
Should you have experience, you can take a mechanic’s scope or screwdriver to check the fuel injection system.
A properly working injector produces some clicking or snapping noise. You probably have a faulty fuel injector when you don’t hear any sound.
Drive Up The Steep Hill To Determine The Engine Performance
The car shuts off when I stop. You can try this solution to quickly determine the problem and have it fixed.
It may sound strange but driving up a steep hill is a good way to inspect the performance of your engine. If you do so and the car is still stalled out, a blocked or clogged fuel filter is the culprit.
Changing a fuel filter is quite straightforward and will not cost too much. The most difficult part is to locate where it is to get to it.
It’s usually in the fuel tank. Call a professional to assist you if you’re not confident in approaching it.
Alert Others
Notifying others when you can’t restart your car is a must.
You have to use your hazard lights to alert other fellows that your vehicle is immobile, and you will stay out of the traffic. The purpose is to keep you safe while investigating the problem.
Seek Help
Lastly, seek all possible help if your car shuts off when slowing down and you can’t do anything. Contact the auto service, so they will help you spot the problem.
Depending on the situation, they can give you a consultation over the phone, and you’re able to go; or the best is the mobile mechanic can come to your place and “rescue” you.
The professionals will test your car, listen for odd noises, and use the OBD2 scan tool to collect the data on stored codes.
This diagnostic tool allows them to access the engine control unit or the transmission control computer and determine what causes the problem and how serious it is.
Conclusion
When a car shuts off when stopped or slowing down, it makes the driver nervous, and overcoming the difficult situation is not really easy. The reasons are various.
If you can not repair it by yourself, turn to assistance from a professional service to identify the root cause and have a proper fixation.