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Q: Why Won't My Car Start?

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Why won't my car start?

A: There are many reasons why your car may not...

There are many reasons why your car may not start. Some common causes include a dead battery, faulty starter or starter relay, fuel pump issues, clogged fuel filter, and computer or sensor issues depending on the year of your vehicle.

A vehicle's engine needs three things in order to run: spark, fuel, and air. If one of these things is not present, the vehicle will not start. There are a few quick tests you can do to help determine why your car is not starting:

  1. Does the vehicle's engine crank over? Try turning the key to the on position and see if the dashboard lights up. If everything lights up, turn on the headlights and see if they are still bright. If they are very dim, you may need to have the battery or the battery cables inspected.

  2. If you turn the key on and nothing lights up, then chances are the battery is completely dead or a major fuse is blown somewhere in the car. This means there could also be an issue with other parts like the fuel pump, fuel filter, spark plugs, or ignition wiring.

  3. Another possible cause for the car not starting is an issue with faulty sensors like the crankshaft position sensor or camshaft position sensor. The computer in today's vehicles receives signals from these sensors to turn on the fuel injectors and deliver a spark to the coils of your ignition system.

  4. In some vehicles, running severely low on engine oil will cause the vehicle to not start because it will not build up enough oil pressure. The vehicle could also have a faulty oil pressure switch, indicated by an illuminated Oil Light on the dashboard.

If you cannot do any of this testing yourself, have a professional technician from YourMechanic come to your home or office to inspect why your car is not starting.

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