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Our dealer said to use 89 octane fuel, that we would be wasting our money using anything higher. Any thoughts on this?

By the way, he also specified anything but BP because of the ethanol content, but aren't several of the oil companies adding ethanol to the mix? What will the ethanol do to the engine?
 

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You won't catch me filling up with anything other than 93!
 

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I think it says on the gas lid to use minimum 91. :confused:
 

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Doesn't sound like this dealer knows what he is talking about - I use SUNOCO premium only at 94 !!!!!
 

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Most engines are optimized for a certain octane. While you won't get any better performance by buying a higher octane (unless it's a turbo), I'm pretty sure that the Audi is not designed for regular unleaded (89 octane). While your car will run fine on 89, you'll be operating in a decreased performance envelope, as the the engine will dial back on timing and other parameters to assure that there is no pre-detonation. This will be more of an issue under harder running conditions (high RPM, high temps, etc.).
 

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Our dealer said to use 89 octane fuel, that we would be wasting our money using anything higher. Any thoughts on this?

By the way, he also specified anything but BP because of the ethanol content, but aren't several of the oil companies adding ethanol to the mix? What will the ethanol do to the engine?
You will loose performance by not running premium fuel.

BTW, BP does not put ethanol into their fuel (unless local regulations require it). This is why they are not a Top Tier rated fuel. This rating requires a minimum of 10% ethanol added to the fuel.

The ethanol addition reduces power and fuel mileage. The advantage is that it burns will less pollution.
 
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