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Discussion Starter · #1 ·
So I just purchased a 13'. It is tune to 91 but I got filled with 89, will this be an issue? Should I try to correct with octane booster? Or will it be fine to finish off this tank and make sure I get the right rating on the next fill?
 

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So I just purchased a 13'. It is tune to 91 but I got filled with 89, will this be an issue? Should I try to correct with octane booster? Or will it be fine to finish off this tank and make sure I get the right rating on the next fill?
Flash back to stage 0 until you run the tank. Never run a lower octane than what the tune is designed for.

Octane boosters are generally not advised either, as they contain chemicals that will coat your cylinders orange and foul plugs.
 

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Discussion Starter · #4 ·
Flash back to stage 0 until you run the tank. Never run a lower octane than what the tune is designed for.

Octane boosters are generally not advised either, as they contain chemicals that will coat your cylinders orange and foul plugs.
Flash back to stage 0 until you run the tank. Never run a lower octane than what the tune is designed for.

Octane boosters are generally not advised either, as they contain chemicals that will coat your cylinders orange and foul plugs.
Let's say I trusted the gas attendant and drove about 60 miles until I realized. Is that significant, or not if I go back to stock tune asap?
 

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2016 ST2, Absolute Black, Monster FMIC, GFB DVX+ BPV, ALEX' Shift Bushings, PCV-OCC, Innovative RMM
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The best advice is flash to stage 0 if you can for safety.

Do you know if it's a Cobb OTS tune, custom, etc.?
And what hardware it was based on (stage idea)?


I unknowingly had a tune on my car and ran a lot of 87 for probably 9 months or more with only Stage 1 green filter, but this was mostly during the pandemic and not putting a lot of miles on the car or running it hard.
I also ran SN+ or better full synthetic oil and didn't drive in ways that would contribute to LSPI.

Recently got an AP3 sooner than planned, thanks to the generosity of another forum member. 👍😎
Stage 1 and Stage 2 93 OTS were on the car when I installed the AP3 and it backed them up, but I'm not sure which one was actually running on the car.

I did check the ECU with Torque app before and it was pulling OAR back towards zero, limiting spark advance on 87. This was when I was trying to figure if it might not actually be stock based on what some said here.

The PO whom I never met left a few receipts, one of which was the cat being replaced under warranty due to some cracked welds. So maybe he had Stage 2 loaded?
(I bought it from a independent dealer that sells a lot of higher end cars and it didn't come with an AP3.)
At any rate, I count myself fortunate and thankful nothing bad happened and again strongly suggest going back to Stage 0.


It's much funner car with FMIC, high flow cat, and Stage 3 93 tune. Get those before exhaust, intake, and cosmetic stuff if you value performance.
 
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