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Discussion Starter · #1 ·
I just got one and I love it!! it's soo roomy, it's tornado red and DSG auto. I'm so excited, I wanna drive all the time. What kind of gas do you guys use?
 

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Discussion Starter · #3 ·
Cool. I knew that, but i was referring to do you use 91 or 93? Would it be okay to use 91 and then every once in a while use 93?
 

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Oh gotcha, sorry about that, I have always used 93 octane because of the fact that is what is available in my area. I have never seen 91 octane. But yeah you could defenitely use 91 octane that is what the 2.0T is rated to use but i have heard from other people they feel a little more zip with the 93 octane. If anyone else knows anything other than this feel free to correct me.
 

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06TRMKV said:
Its gotta be 91 or 93 octane. its the only thing your Fast will like everything else will cause problems down the line.
This is not correct. Your car will run on any grade of unleaded fuel. Your car is set up to perform the best using 91 octane (stock). If you use a higher octane you will reep absolutely no benefit unless you alter the compression to handle the additional octane. Using a lower octane fuel will not harm your engine, not on the Mk5 anyway. However, you will notice a decrease in performance when you are really pushing it.

Hope this helps. You could do some research on your own online to find out exactly how octane works with your engine.
 

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Next contestant - UnitedGray from Delaware, special subject the bleedin' obvious.
 

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UnitedGrayGTi06 said:
93 octane is the best, not 91. Your car will perform better and be more efficient on 93. That is what is is meant to run on.
Where do you see that the Mk5 is meant to run on 93 octane? I am looking inside my fuel door and it recommends 91 octane [(r+m)/2]. Also, the added octane won't benefit you unless your engine is tuned to use it. Octane is what prevents your fuel from spontaneous combusting at lower compression ratios. Tuning your engine will typically result in a higher compression ratio, therefore requiring a higher octane fuel. Without this tuning, you are just wasting your money.

Check out this link: How Octane Works
 

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Discussion Starter · #11 ·
How am I supposed to get 91 octane?! I live near Houston and all we have is 87, 89, or 93.... should I go 2 up or 2 down?
 

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I thought it said that you can use 95 at the highest, and 91 at the lowest (although we all know u can go lower with no problems).
 

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GranTurismoInjection said:
I thought it said that you can use 95 at the highest, and 91 at the lowest (although we all know u can go lower with no problems).
If you're referring to what is written inside your fuel door then the number 95 is for the euro customers where the fuel is graded by RON only.

BTW, has anyone actually done a comparison test to see if the different octane fuels will improve their fuel economy? I have done this several times using Mobil 87 and 93. I drove all highway with each tank and got the same results, +/-5 miles. So, as far as I know, octane doesn't improve your economy when you're just cruising on the highway. Anyone else try this?
 

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Discussion Starter · #17 ·
Wow... the day I got my GTI... what a happy day. It's been almost 8 months. and I'm about to hit 10,000 miles.
 
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