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Old 08-24-2009, 12:28 PM   #1
radz28's Avatar
Drives: Ultra-Grin
Join Date: Oct 2006
Location: Crapramento, Crapifornia
Posts: 13,080
Exclamation Fuse Pull: Low Octane Fuel Fix For L99 and LS3. Reset Fuel Map for High Octane Fuel.

As reported on Homepage.

Okay - after seeing a request for a sticky on how this is done, if someone can post up a couple pics' and exactly how/what to do to correct the power issue with L99s and low octane table, then I'll sticky it here. I think it can go over to the DYI Section too, however, I think it'll do more good here for now. Unless Admin'/Mods' say otherwise, I'll leave it here.

So, again, if someone can snap a few pics', so the DYI'er knows exactly what he/she's doing, and do a quick write-up, and maybe short background on why, I'll change this to a sticky and obviously give credit where it's due.

It should be understood that there is always a risk in DYI'ing, and that this site, Administrators, Moderators, and Members hold no responsibility for any conditions that may arise from performing this on your car; it is completely the responsibility of the DYI'er and owner of the car. This is not a guaranteed fix; only things that some members have shared through their own experimentation.

Waiting on some more confirmation from a member who is working with their dealer to verify the good/bad with regard to this proceedure.

UPDATE: While not officially confirmed, '10 and '11 models do not have modified calibrations to correct this issue. It does NOT appear there is a reflash to correct this. Reliable source(s) say that either a TECH II reflash or this procedure are the only ways to correct this issue. It's unknown if this will change in the future, however, if low octane is detected, the only way for the PCM to get back into the high octane table is outlined a sentence ago.

#PIP4728: Higher Than Expected 0-60 MPH (97 KPH) Acceleration Time- (Nov 4, 2009)
How about that


Some interesting reads:

Does it really work?... There's one test...
  • Make sure the engine and ignition are turned off
  • Locate Fuse Panel in front of the passenger's side front strut tower and pull the cover
  • Remove #5 and #20 (15A fuses) (photo of location below)
  • Let the car sit for at least several hours (overnight is preferable)
  • Install #5 and #20 (15A) fuses
  • Install Fuse Panel cover
  • Restart vehicle and enjoy
Note: Do not unplug the battery. It has no effect.

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