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Q: Do I really need to use high octane fuel or can I use mid grade (occasionally)?

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is it necessary to use the higher octane gas. i sometimes use mid grade and I don't hear a knock or ping. with the price of gas saving a few dollars at fill-up seems like it worth it

My car has 6600 miles.
My car has an automatic transmission.

A: If your vehicle is required to use high oct...

If your vehicle is required to use high octane fuel, then using anything else can cause damage to the pistons and valves in the engine. When you say you cannot hear any pinging when you are using mid grade fuels then you need to be sure since not all pinging can be heard by the human ear. The pinging may be happening so light that you would not be able to hear it. Any pinging is not good to the engine and can burn holes in the tops of your piston. Pinging is the fuel is igniting before the engine wants it to and ignites before the ignition sparks it. This is why it is called pre-ignition. I recommend not using any mid or low octane fuels for this vehicle.

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