How bad is 89 octane for the Evo
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How bad is 89 octane for the Evo
Had a moment of stupidity on Saturday. Went to fill up the car, got 2 gallons in before i realized it was mid grade 89 octane. I finished the fill up with 93 octane (10 gallons). It doesn't feel like the car is knocking or is any slower, I just have to get all the gas out b/f thursday b/c I'm going to AMS to get stage 1 done. How bad is this gonna be for the car and should I run injector cleaner b/f I fill up next time?
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I would think that what you did was completely harmless. The car is designed to run on 91 octane (this is all I can get in California). 2 gallons 89 + 10 gallons 93 = 12 gallons @ about 92.3 octane. You're fine.
#3
If you calculate it your gas tank is averaged at about 92.467 octance, which really won't make much of a difference, just try to use up some gas and fill up on 93, or if your really paranoid, you can put in 1 gallon of unleaded 110 octane and it would more then even it out for you.
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#10
Actually, 89 octane may cause you to throw a code. I did the same thing pretty much, and my car went into limp mode. I also experienced a couple misfires. You might need to get a code cleared before your tune, but that's not a big deal.
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Originally Posted by Hatorade
Actually, 89 octane may cause you to throw a code. I did the same thing pretty much, and my car went into limp mode. I also experienced a couple misfires. You might need to get a code cleared before your tune, but that's not a big deal.
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Originally Posted by mathgeek
I would think that what you did was completely harmless. The car is designed to run on 91 octane (this is all I can get in California). 2 gallons 89 + 10 gallons 93 = 12 gallons @ about 92.3 octane. You're fine.
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Originally Posted by vel53oce
your ecu will compensate and and allow the engine to run on degraded fuel
No it won't. Where does it say this? You will just get misfires and can do damage to the motor.
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Your on it Dayton. My 05 Evo MR indicates a minimum of 93 Octane. What's funny is how it tells you it's OK to use 92 if 93 isn't available. I believe it then says 91 is OK if 92 is unavailable. I gave my local dealer a hard time as I received a voucher to go fill up the tank after I picked up the car. The fuel station I went to (and had the voucher for) only had 92. I ripped on my dealer for violating the owner’s manual with 5 miles on the odometer.