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Discussion Starter · #1 ·
My wife filled up the car last night, and swears that she used 91 octane. Today it seems to run a little more sluggish at high RPMS. If the car in fact had 87 would I hear knocking and pinging, or anything else funky?

Thanks, Hector Lopez
 

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probably not, the knock sensors should back down the timing to compensate for the lower octane.
Mike
 

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Discussion Starter · #3 ·
If it does have 87, will this hurt something? I will start adding 91 as this tank is goes down. Is that the right thing to do?
mottati said:
probably not, the knock sensors should back down the timing to compensate for the lower octane.
Mike
 

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According to the tech who works on my car, eventually the EMS will throw either a code or a light indicating "Improper Fuel Type" or something similar.

:cheers:

Jeff
 

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What I'd do is pick up a bottle of Octane Booster right away, better than safe than sorry :p
 

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Hector-

There are probably a few stations selling 100 octane gas in your area.

http://www.m5board.com/vbulletin/showthread.php?t=50783&highlight=100+octane

Prolly by the time you drove to one, you'd have enough room- 5.66 gallons of 100 added to 12.33 of 87 is 91 octane.

I'd be surprised if there were major driveability issues with JUST 87 octane- advance is retarded, a bit lower HP and it would run a touch hotter (i think)

A
 

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Discussion Starter · #7 ·
It seems as if it won't hurt anything, then I will just add 91 or 100 if I can find it, when I burn through a quarter tank.

Thanks, Hector
 

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Well, I think the issue is that IF you have 'sluggishness' or other issues, it might NOT be caused by the 87 octane (if, indeed, it was 87)... it might be something else.

Maybe you're imagining it- having been separated from the beast while the wife was permitted to operate it- can lead to all sorts of hallucinations.

:)

A
 

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Discussion Starter · #9 ·
Wow, you may be right!:7:
ard said:
Well, I think the issue is that IF you have 'sluggishness' or other issues, it might NOT be caused by the 87 octane (if, indeed, it was 87)... it might be something else.

Maybe you're imagining it- having been separated from the beast while the wife was permitted to operate it- can lead to all sorts of hallucinations.

:)

A
 
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