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Bought 1999 RX - Previous Owner Used 87 - I use 91 - MPG Plummet!

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Old 06-15-12, 02:22 PM   #16
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He's not... The RX300 has knock sensors for a reason, they alert the ECU when the engine knocks, and then the ECU makes the necessary adjustments.

The RX300 engine, 1MZ-FE, has a 10.5:1 compression ratio. That is high compression, and due to that 91 octane or higher is needed.

Last edited by salimshah; 06-15-12 at 03:08 PM.
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Old 06-15-12, 02:37 PM   #17
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OK enough is enough. I will continue to use regular and get great gas mileage. I guess I will just have to take the chance that I destroy my engine.
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Old 06-15-12, 03:12 PM   #18
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Ok guys!

I have made some edits to this thread.

Please feel free to disagree and above all be respectful. And in any argument, there comes a point when the other person is not going to agree. At that point please agree to disagree and move on.

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Old 06-16-12, 09:38 AM   #19
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Agree with Salim..
Also just do what I did.. Try a few tanks full of one take notes, and then try the other and compare your results in your car that you drive under your driving conditions.
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