10 Reasons Why Your Car Won't Start and How PartSource Can Help

Few things are as frustrating as a car that won't start. You insert the key or press the start button, expecting your vehicle to roar to life, and instead, you're met with silence or unsettling mechanical noises. Understanding the underlying reasons can help you troubleshoot the problem more effectively. As one of Canada's leading auto parts retailers with multiple stores across the country, PartSource is here to help you understand what may be the cause.

Regular vehicle maintenance is essential to ensure your car runs smoothly and reliably. Neglecting routine checks and services can lead to unexpected breakdowns and costly repairs. At PartSource, we understand the value of preventive care. By investing a little time in regular maintenance, you can extend the life of your vehicle, improve fuel efficiency, and prevent many issues that could otherwise leave you stranded. Whether it's regular oil changes, brake inspections, or replacing worn-out parts, our experts at PartSource are here to provide you with the best advice and quality auto parts to keep your car in top shape. Here are 10 common reasons why your car might not be starting.

One of the most frequent culprits behind a car that won't start is a dead or dying battery. The car battery is responsible for supplying the electrical power needed to crank the engine and start your vehicle. Over time, all batteries degrade due to various factors such as age, usage patterns, and environmental conditions, leading them to lose their ability to hold a charge effectively.

Symptoms: If your car battery is the issue, you might notice:

• No lights on the dashboard: When you turn the ignition key or press the start button, none of the dashboard lights or indicators light up, indicating a lack of electrical power.
• No sound or a clicking sound when you turn the key: If you hear nothing or just a repetitive clicking noise when you attempt to start your car, it's often a sign that the battery doesn't have enough power to engage the starter motor.

• Jump-start the car using jumper cables: Connect your car's battery to another vehicle's battery using jumper cables. Start the working car and let it run for a few minutes before attempting to start your own vehicle. This can provide enough charge to get your car running. You could also use a booster pack that is safer and  with you whenever you need it
• Check for corrosion on the battery terminals: Inspect the battery terminals for any signs of white or blue-green flaky deposits. Corrosion can impede the connection between the battery and your car’s electrical system. If you see corrosion, clean it off carefully using a mixture of baking soda and water with an old toothbrush.
• Replace the battery if it’s old or damaged: If your battery is more than 3-5 years old, or if it shows visible signs of damage (like a swollen casing or leaking fluid), it's probably time for a replacement. A new battery can ensure reliable starting power.

The starter motor plays a crucial role in your vehicle's ignition system. It is responsible for turning the engine over and initiating the combustion process that starts your car. When the starter motor malfunctions, it can prevent your engine from starting, even if your battery is fully charged and in good condition.

Symptoms: If you suspect a faulty starter motor, look for these signs:

• A clicking sound when turning the key: If you hear a single or rapid clicking noise when you try to start your car, it might indicate that the starter motor solenoid is trying to engage but cannot turn the motor.
• The engine doesn’t turn over: When you turn the key or press the start button, nothing happens, meaning the engine doesn't crank at all, pointing towards a potential issue with the starter motor.

• Lightly tap the starter motor with a hammer: Sometimes, lightly tapping the starter motor with a hammer or wrench can temporarily jolt it into working. This isn't a permanent fix but can help you start your car in an emergency. This only is an option if your starter motor is easily accessible replace starter motor by a professional.
• Test the starter motor with a multimeter: Use a multimeter to test the electrical connections of the starter motor. This can help determine if there’s an issue with power delivery to the starter.
• Replace the starter motor: If tapping and testing indicate that the starter motor is indeed faulty, see a professional about replacing it with a new or refurbished unit. That would be the best long-term solution for piece of mind.

Your engine relies on a steady supply of fuel to run, and any disruption in this system can prevent your car from starting. Common issues include a clogged fuel filter, a faulty fuel pump, or simply an empty gas tank. These problems can impede the flow of fuel to the engine, leading to starting difficulties.

Symptoms: If you suspect fuel system issues, watch for these signs:

• Engine cranks but doesn’t start: The engine turns over when you try to start it, but it fails to catch and actually run.
• Lack of sound from the fuel pump when the ignition is turned on: Normally, you should hear a faint whirring sound coming from the fuel pump when you turn the key to the "on" position before starting the engine.
• Poor fuel economy: Decreased fuel efficiency can indicate problems with the fuel filter or pump, affecting your car’s overall performance.

• Check if there’s fuel in the tank: Ensure that your gas tank isn’t empty. Sometimes the simplest explanation is the correct one.
• Listen for a whirring sound from the fuel pump: When you turn the ignition key to the "on" position (without starting the car), listen for a brief whirring noise from the fuel pump. If you don't hear it, there might be an issue with the pump.
• Replace clogged fuel filters: Inspect and replace any clogged or dirty fuel filters that could be restricting the flow of fuel to your engine.
• Get your fuel pump inspected and replaced if faulty: If you suspect that the fuel pump is not functioning correctly, have it inspected by a professional. If necessary, replace it to ensure proper fuel delivery.

The ignition switch is a critical component that enables you to start your car and control power to various electrical accessories, such as lights, radio, and the air conditioning system. If the ignition switch malfunctions, it may prevent your car from starting altogether, even if other parts of the vehicle are in good working order.

Symptoms: If you suspect issues with your ignition switch, look out for these signs:

• Dashboard lights don’t come on: When you turn the key to the "on" position, none of the dashboard lights or indicators illuminate. This indicates that the ignition switch might not be sending power to the vehicle’s electrical systems.
• No response when turning the key: When you turn the key in the ignition, there is no cranking sound or any response from the engine at all, signifying a potential problem with the ignition switch.

• Wiggle the key while in the ignition: Sometimes, gently wiggling the key while it’s in the ignition can help make a connection and start the car. This might indicate a worn-out or faulty ignition switch.
• Replace the ignition switch if it’s worn out: If wiggling the key doesn't work or if you frequently have trouble starting your car, it may be necessary to replace the ignition switch. An experienced mechanic can diagnose and replace this component to ensure your vehicle starts reliably.

Modern vehicles often come equipped with engine immobilizers as a theft deterrent. This system is designed to prevent the engine from starting without the correct key or key fob. If there’s an issue with the immobilizer or if it fails to recognize your key, it can stop your car from starting, even if everything else is in working order.

Symptoms: If you suspect engine immobilizer issues, look for these signs:

• Dashboard warning lights indicating immobilizer issues: You might see specific warning lights on your dashboard related to the immobilizer system.
• Key symbol flashing on the dashboard: A flashing key symbol or security light on the dashboard typically signifies that the immobilizer does not recognize the key, preventing the engine from starting.

• Use your spare key to start the vehicle: Sometimes, the issue may be with your primary key or key fob. Trying to start your car with a spare key can help determine if this is the case.
• Reset your immobilizer system according to manufacturer guidelines: Refer to your vehicle’s owner manual for specific instructions on how to reset the immobilizer system. This often involves a sequence of steps that can reset and re-sync the system.
• Consult a professional for further diagnosis: If you’re unable to resolve the issue yourself, it’s best to consult a professional mechanic or dealership. They have specialized tools and knowledge to diagnose and fix complex immobilizer problems.

Although the battery supplies the initial power to start your car, the alternator is responsible for recharging the battery and powering the electrical systems while you're driving. If your alternator is failing, it may not effectively charge the battery, leading to a dead battery and a car that won’t start.

Symptoms: If you suspect alternator problems, look for these signs:

• Dim headlights: Your headlights may appear dimmer than usual, especially when idling, due to insufficient electrical power.
• Electrical issues while driving: You might experience flickering dashboard lights, malfunctioning electronic accessories, or other electrical problems while driving.
• Battery warning light on the dashboard: A battery-shaped warning light on your dashboard often indicates issues with the alternator or charging system.

• Test alternator output with a multimeter: Use a multimeter to check the voltage output of the alternator. A healthy alternator should typically produce between 13.5 and 14.5 volts when the engine is running.
• Replace failing alternator:If testing reveals that your alternator is not producing adequate voltage, it likely needs to be replaced. An experienced mechanic can handle this replacement to ensure your vehicle’s charging system operates correctly.

Ignition system issues could relate to the coils, sensors, engine control module or spark plugs. Spark plugs are essential components that ignite the air-fuel mixture within each cylinder of your engine. If the spark plugs are faulty or worn out, they can fail to create the necessary spark for proper combustion, which can prevent your car from starting.

Symptoms: If you suspect issues with your spark plugs, look for these signs:

• Engine cranks but doesn’t start: The engine turns over when you try to start the car, but it fails to actually ignite and run.
• Poor acceleration: When the vehicle was running, You may notice sluggish acceleration or a decrease in overall engine performance.
• Engine misfires: The engine might run irregularly or intermittently, often accompanied by unusual sounds and vibrations.

• Inspect spark plugs for wear and tear: Remove and examine each spark plug for signs of wear such as erosion, deposits, or damage. A healthy spark plug should be relatively clean and intact.
• Replace spark plugs if necessary: If any spark plugs appear worn out or damaged, replace them with new ones. It’s generally a good idea to replace all the spark plugs simultaneously to ensure even performance across all cylinders.

The timing belt is a crucial component that ensures your engine's valves open and close at the proper intervals by synchronizing the rotation of the camshaft and crankshaft. If the timing belt breaks or skips a gear, your engine won’t operate correctly or may fail to start altogether.

Symptoms: If you suspect timing belt issues, look for these signs:

• Unusual noise before stalling: You might hear a ticking or slapping noise from the engine just before it stalls. This can indicate that the timing belt is loose or damaged.
• Engine turns over faster than normal without firing up: If the engine cranks unusually fast but doesn’t start, it may indicate a broken timing belt, as the normal resistance provided by the synchronized components is absent. 
• Other Internal mechanical issues such as broken valves, lifters, pistons, may also cause an engine not to start. If there are unusual noises coming from the engine when trying to start the vehicle, have a professional inspect and diagnose the problem

• Check for visible damage on the timing belt: Inspect the timing belt for any signs of wear, cracks, fraying, or missing teeth. These issues can indicate that the belt is at risk of failing.
• Replace timing belt as per manufacturer’s recommendation: Timing belts should be replaced according to your vehicle manufacturer’s guidelines, typically around every 60,000 to 100,000 miles. Preventive replacement can help avoid unexpected failures.

Modern vehicles rely heavily on computer systems, particularly the Engine Control Unit (ECU), to manage and control various engine functions. If there’s an issue with the ECU or related systems, it could prevent your engine from starting by sending incorrect signals or failing to communicate properly with other components.

Symptoms: If you suspect computer system malfunctions, look for these signs:

• Check engine light stays on constantly: A persistent check engine light may indicate underlying issues with the ECU or related sensors.
• Diagnostic Trouble Codes (DTCs) present when scanned: When you scan your vehicle with an OBD-II scanner, you may find specific diagnostic trouble codes that point to issues with the computer systems.

• Use an OBD-II scanner to read diagnostic trouble codes: Connect an OBD-II scanner to your vehicle’s diagnostic port to retrieve any trouble codes. These codes can help identify specific issues related to the computer systems.
• Reset ECU by disconnecting and reconnecting the battery after a few minutes (temporary fix): Disconnect the negative terminal of your car’s battery, wait for about 10-15 minutes, and then reconnect it. This can temporarily reset the ECU and clear minor glitches. However, this is not a permanent solution and professional diagnosis may be required for persistent issues.

Many electrical components in your vehicle depend on fuses and relays to distribute power properly. If these components fail or blow out, they can interrupt essential circuits, including those needed to start your engine. A faulty fuse or relay can prevent the necessary electrical current from reaching critical parts of the starting system.

Symptoms: If you suspect issues with fuses or relays, look for these signs:

• No response when turning the ignition key: The engine doesn’t crank or respond at all when you try to start the car.
• Electrical components not working correctly (lights, radio): Other electrical systems, such as headlights, interior lights, or the radio, may not function properly due to a blown fuse or malfunctioning relay.

• Locate the fuse box using the owner's manual: Refer to your vehicle’s owner’s manual to find the location of the fuse box. Most cars have multiple fuse boxes located under the dashboard, in the engine compartment, or in other accessible areas.
• Inspect relevant fuses and relays & replace if blown/malfunctioning: Examine the fuses and relays connected to your car’s starting system and other problematic electrical components. If you find any blown fuses or faulty relays, replace them with new ones of the same amperage and type.