The vehicle owner wants the efficient working of the vehicle. If your car engine starts then dies immediately, it means there is something wrong with your car. The car engine may die due to different reasons such as insufficient fuel, low coolant level, engine overheating, clogged air filter, clogged fuel filter, or bad crankshaft.
As you identify the reason for the problem, then immediately fix it. This article mainly explains the causes of a car that starts and then shuts off.
Common Reasons Why a Car Starts Then Dies
The most common reason for a car to start but then immediately dies is usually a lack of fuel being delivered to the engine. This can often be caused by a faulty fuel pump or a blocked fuel filter. Additionally, issues with the car’s immobilizer not identifying the key can also lead to such a problem.
Following are the major causes of why a car starts then shuts off:
1) Bad Idle Air Control Valve
The Idle Air Control (IAC) valve plays a big role in the efficient working of the car. This valve is installed to regulate the car’s air/fuel mixture at idle. It also helps to manage the idle speed when the engine load changes, such as turning up the radio, turning on the headlights, or turning on the air conditioning.
The failure of the idle air control valve can result in unstable idle speed or a complete stall of the vehicle. This applies in particular to cold start conditions.
In case of a defective IAC valve, you may continue to run the engine by refueling. This is a temporary fix, but it may mean something other than being stuck and safely getting to your destination.
As the idle air control valve goes bad, you must fix it immediately. Clean the valve to see if the problem goes away. If your vehicle is still producing problems, then contact the mechanic.
Read More: Bad IAC Valve Symptoms and Causes
2) Insufficient Fuel
Insufficient fuel or low-quality fuel is one of the most common reasons due to that your car starts then shuts off. The proper supply of fuel is very important for the efficient working of the car.
As the fuel level becomes low than the required level of the vehicle, the vehicle starts creating issues and sometimes doesn’t start. Therefore, add more fuel to the fuel tank before driving.
However, a low fuel level is easy to find. Install the fuel pressure gauge on the fuel rails or carefully loosen the screws to check the fuel pressure when starting the engine.
Your vehicle may also face fuel shortage issues due to leakage. You may also have a faulty:
- Fuel pressure regulator
- Fuel pump
- Fuel rails
- Fuel pump relay
3) Vacuum Leak
A vacuum leak is a hole that permits air to enter without weighing the engine down. It is located behind the MAF (mass air flow) sensor in the air intake system of the car. It deviates from the desired air/fuel ratio and ensures the lean running of the vehicle.
If the fuel-air mixture is too lean, the vehicle may shake at startup and then dies very quickly.
In many cases, the car continues its run with a slight vacuum leak. If the leak converts into the worst condition, the fuel injector will not have the ability to keep up with all the additional unmetered air without the system to burn fuel properly in the combustor.
If you open the hood, you might find something that is clearly out of place, such as a disconnected or broken vacuum line. If there aren’t immediately obvious leaks, you can do a smoke test to check the exact cause of the leak.
4) Dirty Fuel Filter
The fuel filter ensures contaminated free fuel supply to the vehicle engine. It removes contamination from the fuel and then supplies it to the engine. If your car stalls after you turn the ignition on, it means you have fuel-related issues. Fuel filters are ubiquitous and cause low fuel pressure.
The proper cleaning and replacement of the fuel filters are vital for the proper working of the vehicle.
The replacement time scale of the fuel filters depends on the distance that the vehicle travel and the vehicle model. If you don’t replace it for a long time, it may be clogged.
Fuel filters are usually easy and inexpensive to replace. If the fuel pressure is low, it’s worth replacing.
Read More: Bad Fuel Injector Symptoms and Causes
5) Bad Crankshaft/Camshaft Position Sensor
A bad crankshaft position sensor is one of the major reasons of a car starts then dies.
The crankshaft and camshaft position sensors of your vehicle tell the powertrain control module (PCM) about the position of the camshaft and crankshaft at all times. This permits the PCM to adjust the spark plug firing (ignition timing) according to the position of the revolving parts.
If the PCM does not receive a clear signal, the engine may not start or may freeze shortly after starting.
If the camshaft or crankshaft position sensor doesn’t send the signal, the PCM turns on the check engine light. This check engine light indicates a specific code. Try to read this code and find the exact wire that is creating the problem.
Check the crankshaft/camshaft sensor connectors to ensure the wires are free of corrosion or bare metal.
6) Bad Fuel Injectors
The fuel injector is employed to inject the fuel into the combustion chambers. It increases the fuel pressure and then injects it into the combustion chambers. The injector’s function is to deliver the precise amount of fuel according to the combustion chamber requirements.
If the fuel injector fails, the engine can run on fewer cylinders, and fuel pressure can be lower if one cylinder is left open.
First, touch the injectors with your hand to feel if they generate a clicking noise. If you don’t hear a clicking noise, one of them may be defective.
Read More: Bad Fuel Injector Symptoms and Causes
7) Faulty Spark Plug
As the spark plug fails, it will not generate a spark, and the air-fuel mixture will not ignite; due to that, your car will not move. This can lead the car to start for a few seconds, but the weak sparks will cause it to backfire too much, and the engine will die immediately.
Read More: Bad Spark Plug Symptoms and Causes
8) Ignition Issue
The ignition system has the responsibility to produce a spark that burns the air-fuel mixture in the combustor.
If there is a problem with the ignition system (e.g., a faulty spark plug), then the system will not properly produce a spark to combust the air-fuel mixture in the combustion chamber properly. In such a condition, your car dies as you start it.
For the efficient working of the ignition system, your vehicle battery must have a connection, and the terminals are not corroded. If the terminals are corroded, then try to clean them. Use battery terminal cleaners to clean the corroded terminals.
Your ignition coil or spark plug wire must be properly connected to each spark plug. If the spark plug wire is pulled out or broken when the engine is struggling to keep running on fewer cylinders, it can cause a misfire and usually stall.
9) Bad EGR Valve
An EGR valve helps to control the emission of harmful exhaust gases. When the EGR valve goes bad and stays open, too much air may enter the intake manifold.
This excessive air can lead the air-fuel mixture to become too lean which causes your vehicle starts and then dies after a few seconds.
Read More: Bad EGR Valve Symptoms and Causes
10) Bad PCM
The engine control module (ECM) or powertrain control module (PCM) is a computer system that helps to control different functions of the engine, such as the fuel injection system and cooling system. The car requires a precise amount of fuel to run. As the PCM/ECM goes bad, the car dies after starting.
The PCM uses different sensors to control the function of different engine parts. After some duration, the sensor can fail, and incorrect information is passed to the PCM. In such a condition, you should contact a specialist.
Read More: Bad PCM Symptoms and Causes
11) Damaged Fuel Pump
The fuel pump delivers fuel from the fuel tank to the engine. Leaks in the fuel injection system or fuel pump can generate different issues with the internal combustion process. The engine needs a precise amount of fuel and air to mix for the combustion process.
If the fuel pump is leaked, then the combustion chamber may not be getting the right amount of fuel. This may be enough to start the engine but may not keep the engine running.
Read More: Bad Fuel Pump Symptoms and Causes
12) Bad Carburetor
The carburetor is most commonly used in petrol engine vehicles. It is used to mix the air and fuel according to the combustion chamber requirements. If the carburetor fails for any reason, it doesn’t efficiently mix the air and fuel and leads the engine to run too lean or too rich.
Read More: How to clean a Carburetor?
13) Faulty Anti-Theft Alarm System
A bad anti-theft alarm system can be another common cause of a car that starts and then shuts off immediately. As the anti-theft system activates, your car stops supplying power to the fuel pump, which results in the fuel rail becoming pressurized with fuel. As mentioned before, this could cause the vehicle to start but only for a short time.
Your vehicle dashboard contains a key icon. It appears and then turns off a few seconds after the ignition is activated if your car has a factory-installed anti-theft alarm system. If this icon does not go off, lock and unlock the car before trying again. If the icon is still illuminated, there may be an issue with the vehicle key.
In the case of third-party anti-theft alarms, there could be problems with the device itself or the remote control. In such situations, the immobilizer system may require reprogramming.
How to fix a car that starts and then dies?
You need to repair or replace one or more of the below-given parts to fix the issues related to a car that starts then dies:
- Replace the faulty Idle Air Control Valve
- Check the fuel level and add more fuel if needed
- Ensure the proper maintenance of the vehicle
- Fix the vacuum leaks
- Clean or replace the dirty fuel filter
- Replace the faulty crankshaft position sensor
- Replace the bad fuel injectors
- Replace the faulty spark plugs
- Fix the issues related to ignition
- Replace the bad EGR valve
- Replace the faulty PCM
- Replace the faulty fuel pump
- Replace the faulty carburetor
- Replace the bad anti-theft alarm system
What to do when your car starts and then dies?
If your vehicle starts and then immediately stalls, the first thing you need to verify is whether your immobilizer recognizes the car key. Look for the key icon on your dash and ensure it vanishes a few seconds after igniting the engine. Following this, inspect the fuel pressure. If this pressure is insufficient, it’s time to check the fuel pump and fuel filter.
Can a bad battery cause a stalling engine?
Yes, a deteriorating battery may also lead to a stalling engine if its condition is seriously poor. If your battery is not able to deliver sufficient power to the engine, it may lead to different problems, stalling being one of them. If your car is struggling to start or has been stalling more frequently, it is advisable to check your battery.
Can I unclog a fuel filter?
Though it’s possible to clean a clogged fuel filter, it’s typically not advised. A fuel filter is usually inexpensive, and trying to clean it can cause more issues and frustrations than simply replacing it with a new one.
Why does my car start and stop?
The stop-start system, or the start-stop system of a vehicle, automatically turns off and starts the engine again to reduce the idle time of the IC engine. This helps in reducing fuel consumption and emissions.
Why does my car turn off immediately after starting?
The most common and apparent reason for a car starting and then stopping is a low fuel level in the engine. This happens due to inadequate fuel in the fuel rails and insufficient fuel pressure to sustain engine operation.
Why does my car start then sputters and shuts off?
If your car starts, then sputters and shuts off, it often points towards issues with your fuel, exhaust system, or dirty or damaged components. In the case of an internal combustion engine, incomplete combustion of the air-fuel mixture can lead to sputtering. While a sputtering engine might not seem like a major issue at first, if left unchecked, it often results in expensive repairs.
Why car starts then dies with no check engine light?
Another prevalent and clear-cut reason for your car starting and then stalling is a deficiency of fuel in the engine. This issue arises due to an insufficient amount of fuel in the fuel rails, coupled with a lack of fuel pressure needed to sustain engine operation.
Can a bad spark plug cause a car to shut off while driving?
Yes, an engine with a bad spark plug may temporarily stop and then return to normal operation. This could happen during driving, and the engine might produce a rough sound while idling. Worn-out spark plugs may cause your vehicle’s engine to misfire due to their inability to ignite the fuel/air mixture efficiently.
Why my car starts then dies, and won't start again?
A typical cause for your car starts for a second then dies, and won’t start again could be a depleted battery. Your vehicle relies on power from the battery for ignition. But if the vehicle starts and then instantly dies, the problem may be related to a lack of charging or a faulty battery.