I put a little more than a half a tank of 89 octane in my car when i drove it home on saturday and just filled it up with 89 again and just read the manual and saw it should have 91 or higher...I am going to the store to buy octane booster right now....Did i hurt my baby?

did you just cruising or were you pushing it and boosting everywhere?

Don't bother with the octane booster you'd neen a case to even do anything. I'm sure the ECU was able to correct for it. Damn things are pretty rich out the box.

Just drive it out of boost until next fill up you'll be fine

It's really not that big of a deal. The engine has a knock sensor which will cause a lower octane map to be used. Of course it's not great for your engine to knock at all but once or twice shouldn't cause any long term damage. Just drive it easy for the rest of the tank.

You're fine if you weren't driving spirited. Here in CA all we got is 91 and some areas E85 and Racing Fuel.

i've put in 83 only because it was that or a push... drove it nicely and it drove okay. Like the boys said already, don't be trying to showoff just drive it like its grandmas for a bit and shell be fine.

i got on it a little bit once or twice but i honestly was just cruising at 15% throttle for most of the time...I put in some Lucas oil octane booster and am just going to baby it like all of you have recommended!!! I probably didnt need the octane booster but it cant hurt.....From now on I will be using the best fuel I can find which is Sunoco ultra 93...I have 100 octane race fuel right down the street but it is like $8 a gallon and i just cant see justifying that without some MAJOR modifications...Thanks again for the info everyone...Gotta say I love this place...very helpful!!!

Thats nothing! I ran my Evo on E-85 on a 91 oct map for six miles. I even went on the highway.

It drove fine but I couldn't boost at all.

Luckily here all I see is 93 Octane and the normal stuff.

not a big deal, just drive easy and let the tank empty

^+1

Assuming its stock, you could run 89 in it for the life of the car. Premium is reccomended for optimal performance.

This.

I accidentally ran 89 for a full tank and had no issues but did not push the car at all.

Just drive like a granny until the tank is done. You'll be fine.