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OOPS! What should I do?

1171 Views 5 Replies 4 Participants Last post by  greg
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!


/Greg - Master Airhead
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Octane booster will only add to the problems. Try using that gas up ASAP (leadfoot it!). Hope it works out ok.

Best solution is fill again at half a tank and dilute the low octane with high test.
I see Bay Area folks responding. Any of you M5'ers going to join Greg on the 21st?
Hope to. Still have to work out details.

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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