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Discussion Starter #1
I just got gas. Only after replacing the nozzle in the pump did I realize I just filled my tank with 87 Octane instead of the good stuff.


AND I have a 200+ mile trip up to the mountains tomorrow.

Does the M5 have knock sensors (which would automatically retard timing/reduce throttle/adjust mixture) to prevent knock? Will I be OK? Should I add in a bottle of that after-market octane booster stuff, or might it do more harm than good?

Informed suggestions, please!

Thanks

/Greg - Master Airhead
 

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Best solution is fill again at half a tank and dilute the low octane with high test.
 

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I see Bay Area folks responding. Any of you M5'ers going to join Greg on the 21st?
 

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Discussion Starter #6
Closing comments - I pushed the car hard with the bad gas - no ill effects except a little down on power. Evidently the engine management computer just does the right thing, which is probably to retard the timing a little bit.

So - in case this ever happens to you - don't worry about it!
 
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