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10 Reasons Why Your Car Won’t Start

Vehicle ownership definitely has its ups and downs. The day you drive your shiny, new baby off the lot at the dealership, your first road trip together, and the day you send in your last loan payment are some of the best days of ownership. Then, there are those bad days, too; the day you notice the first scratch or dent on your door, your first flat tire together, and the day you find yourself asking, “why won’t my car start?” How could your car do this to you?

These days when a car won’t start, it seems almost unfair. Vehicles are so intelligent; they should warn us when they don’t want to start. While that may be something developed in the future, for now, we’ve compiled a list of the top ten reasons why your car is not starting.

1. Dead Battery

More often than not, batteries die without much warning. If the battery is weak, but not completely out of charge, there is a chance that the starter may turn over slowly. There are several reasons that cause batteries to die including lights left on by mistake, loose wiring, or failure due to age or defect.

Tips on how to extend your car battery life

2. Loose or Dirty Battery Terminals

While your battery may not actually be dead, it might be something as simple as loose or dirty battery terminals. When your car won’t start, open the hood and ensure the clamps attached to the battery are tight and secure. If they are a bit loose, tighten them up and then attempt to start your car again. Additionally, corroded terminals can weaken the connection making starting difficult. Check for corrosion such as white or greenish buildup on or around the battery posts. Cleaning the corrosion off the area may be all you need to do to get your car started again. While wearing gloves to protect your hands from battery acid, mix one tablespoon of baking soda to one cup of water and stir. Using a wire brush and the baking soda mixture, scrub to remove all buildup. Once complete, wipe the area down with a damp rag. In the event that the corrosion has come between the cable and battery post, the cable will need to be removed and cleaned properly. You can prevent this from occurring with your vehicle by keeping the cables clean.

3. Faulty Alternator

The job of the alternator is to keep the battery charged and supplies electricity to the vehicle’s internal computer for normal operations. When the alternator is in failure, it will often give out warning signs such as slow cranking and dimming headlights. A faulty alternator will not be able to produce adequate power to send to the battery. The alternator is attached to the engine and is driven by the serpentine belt. If the belt is worn or has slipped, your alternator will struggle to function. When this occurs, most often you will receive notification by a light on the dashboard.

The alternator could cause a car not to start

4. Worn Spark Plugs

Most vehicles today can go about 100,000 miles before they’ll need new spark plugs. If your vehicle has reached the 100,000 mile mark, it’s a good idea to replace them. Spark plugs that are in failure will produce symptoms that include rough idling, poor acceleration, misfires, poor fuel economy, a check engine light on, and difficulty starting.

5. Failed Ignition Switch

If you’ve confirmed your battery is working, but the car still doesn’t turn over after several attempts, the ignition switch may be the source of your problem. If the no start issue is accompanied by flickering dashboard lights, no noise from the engine when attempting to start, or you’re unable to the turn key, it’s possible the ignition switch that has failed.

6. Starter Has Gone Out

The starter is exactly what it sounds like it is. It starts your engine. It’s an electrical motor connected to the battery that sends the internal components in the engine into motion once the ignition switch has been activated. Once the engine is set in motion, the starter’s job is complete. Once the starter has failed, the engine will not be able to crank properly or at all. If you attempt to start your vehicle and hear a clicking sound, a failed starter is likely at fault.

7. Clogged Fuel Filter

The fuel filter is a vital component in the process of delivering fuel to your vehicle’s engine while also protecting fuel injectors. The fuel filter traps contaminants including dirt and other fine particles from entering and possibly damaging the engine. Over an extended period of time, however, the fuel filter can become clogged reducing the flow of or blocking fuel from getting to the engine to complete the combustion process.

Car Won't Start? Could be a clogged fuel filter

8. Failed Fuel Pump

You know your car needs gas to burn as part of the combustion process. It’s the fuel pump’s job to transfer that fuel from the gas tank to the engine, with the right amount of pressure to accommodate the vehicle’s speed and performance. When the car is started, the fuel pump is set into motion and pressurized to send fuel to the engine. A failed or exhausted fuel pump will prevent your vehicle from running or cause it to run very poorly. 

9. Running on Empty

Have you run out of gas? Just as noted above, your car needs gas to burn and if the tank is empty, you won’t be going too far. Vehicles today let us know that we have a certain number of miles until the tank is empty, however, that number is strictly a calculation based on the estimated amount of fuel in your tank and your current speed. It’s not an accurate number to rely on. In fact, letting your fuel drop down past ¼ tank can cause damage to your fuel pump, as fuel keeps the pump lubricated and prevents them from burning out. Keep an eye on your fuel gauge!

10. Electronic Malfunctions

Technology is both a blessing and a curse. Remote keyless entry and starting modules can cause troubles from time to time. Many vehicles today have a start button as opposed to an ignition key to start the vehicle. The start button receives a coded signal from the proximity key. If your vehicle fails to start, it’s possible the battery in the key fob itself has died. If you’ve replaced the battery and it still doesn’t work, the key fob may be defective, which make things a bit more complicated. You’ll need to seek out a professional to connect to your vehicle’s internal computer and program a new key fob.