My car requires premium gas, but I filled the tank with a lower grade gas, causing a knocking sound. I then put in an octane additive. How long does it take for the knocking to go away? – Brett Octane ...

Octane ratings refer to the stability of fuel, and dictate at which pressures the fuel will spontaneously combust. Engine knocking can happen when the octane rating is too low, resulting in pinging ...

With rising petrol pump prices, can I downgrade from the usual 95- and 98-octane fuel to 92-octane to cut cost? With the way petrol prices are spiking, there is good reason to consider cheaper, ...