Is this a generic question or specific to a certain vehicle? If a certain vehicle is it a stock Chevy six? Generally speaking pinging can be caused by a hot spot in one or more cylinders, too low octane for the compression ratio and advanced timing. There may be more causes I'm not aware of.
Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.
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