Can you use lower octane gasoline when it requires 92?

You may be able to change octanes between seasons ( reduce

octane in winter ) to obtain the most cost-effective fuel without loss of

driveability.

The manufacturer's recommendation is conservative, so you may be able to

carefully reduce the fuel octane. The penalty for getting it badly wrong,

and not realising that you have, could be expensive engine damage. If you use a fuel with an octane rating below the requirement of the engine,

the management system may move the engine settings into an area of less

efficient combustion, resulting in reduced power and reduced fuel economy.

You will be losing both money and driveability. If your vehicle does not have a knock sensor, then using a fuel with an

octane rating significantly below the octane requirement of the engine means

that the little men with hammers will gleefully pummel your engine to pieces. The bottom line is that you might be able to move to a 89 octane level fuel but it will cause a loss of power & mileage, and may cause engine damage. My advice is to use the exact octane fuel listed in your owner's manual. That way you get to most the engine has to offer, in power & mileage. And you do not take a chance of ending up with engine damage.