What grade of gas do you put in your SI?

What fuel do you use?

  • Regular

    Votes: 25 7.2%
  • Midgrade

    Votes: 12 3.5%
  • Premium

    Votes: 310 89.3%

  • Total voters
    347

ice raptor

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When i purchased my SI i was told that the vehicle was able to run on regular OR premium. Now i know a thing or two about cars and it seemed a little off hearing this...But id like to hear from you guys. What fuel do you put in your SI's?

 

grumpyguy6

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I always use the manufacturer recommended gas grade. In this case, Premium, although I'm pretty sure the full tank I got when I took delivery was regular. I waited until my low gas light came on before filling it up to get rid of as much of it as I could (normally I don't like to let it get below half).
 
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ice raptor

ice raptor

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I always use the manufacturer recommended gas grade. In this case, Premium, although I'm pretty sure the full tank I got when I took delivery was regular. I waited until my low gas light came on before filling it up to get rid of as much of it as I could (normally I don't like to let it get below half).
Yeah i believe that was the same for me. I knew that high compression engines needed premium fuel so it made me a a bit confused when he told me that. Thanks for the info! Im doing the same and waiting till its almost all gone before filling her up with a nice tank of premium. My last car took premium as well so its not a big shocker for me.
 

rushwal

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That first free tank of gas was regular for me... Sales lady said "Yes, it takes Regular gas". Premium ever since.
 


jakabony

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Premium here too. I tried out 87, 89 and 93. Overall, the car runs better and gets better gas mileage (2-4mpg) with 93.
 
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ice raptor

ice raptor

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I think all i have here thats near me is 91. But a lot better then the regular thats in the tank right now. So it gets better MPG with premium as well?
 

jakabony

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I think all i have here thats near me is 91. But a lot better then the regular thats in the tank right now. So it gets better MPG with premium as well?
It appears that way. Was averaging 34-36mpg with a tank of regular, 37-38mpg with premium
 
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ice raptor

ice raptor

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Wow thats pretty nice. I was planning to do premium but this has pretty much sold me on it regardless.
 

TophersSI

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When i purchased my SI i was told that the vehicle was able to run on regular OR premium. Now i know a thing or two about cars and it seemed a little off hearing this...But id like to hear from you guys. What fuel do you put in your SI's?
Only premium!
 


skullmurdoc

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The engine is build with premium in mind. While it work with regular I don't think it's the best for reliability.
In the manual it states that with regular ECU will pull timing to protect itself because of knock.
 

T_A_H

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91, which is the highest grade a available at the pump where I live.
 

Monocacy

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It appears that way. Was averaging 34-36mpg with a tank of regular, 37-38mpg with premium
I had a similar experience. Spouse kindly volunteered to fill the tank, I forgot to tell her what kind of gas. Probably around 3-4 mpg lower on a tank of regular versus premium. Presumably, as stated above, because the ECU changes the timing to prevent engine knock.

For my driving (crowded interstate highway commuting) I have not noticed a difference in mileage or performance between 89 and 93 octane fuel.

I hear of many folks using 91 octane fuel. Oddly, we usually have 87, 89, or 93 octane available.
 

TheRealWizzy

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Premium only in fact i drive a couple miles out of the way to get 93 over 91. Luckily for me i know the guy who took my car to do the first fill up at the dealer so i got premium fuel from the start.

 

 
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