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Can I run 87 or 89 octane fuel in my Mazda CX-7?
We recently purchased a low mileage Mazda CX-7 as a second car. The 244HP 2.3-litre turbo engine is very thirsty and the manual calls for 91 octane fuel. Can 87 or 89 octane be used without harm, other than a small loss of performance?
Asked on 24 August 2013 by BH, Cobourg, Ontario, Canada
Answered by
Honest John
Octanes are different in Canada and the US. The UK equivalents are 95RON and 97-99RON. But if you use lower octane fuel you will not only gum up the engine fuel system and lose about 20PS in power, you will suffer an increase in the amount of fuel consumed which will make running the car more expensive. In my experience, the higher the octane you use, the more efficiently the engine will run and the less fuel it will use.
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