Fuse Pull: Low Octane Fuel Fix For L99 and LS3. Reset Fuel Map for High Octane Fuel.

[jabbar]

Would I have to do this if the car has 87 octane in it and I will be using 93? After installing a new cold air intake and exhaust?

I am buying an LS3 and it only has 18 mi. on the odometer but I think the dealer has filled it up with 87 gas already :( And I will try to put in the intake and exhaust before hitting 100 miles.

[CamaroSS2010]

OK - So I have had my L99 since 6/31/09 - I know for a fact that when I picked it up at the dealer - they put 87 octane in it.
I had read about this fuse pull since it began.
But I was not sure if if my car was affected.
I have had the following mods done to it:
Borla catback exhaust
Rotofab CAI
Dynomax LT Headers w/Hi-flo Cats
and a tune.
I have just read a post (above) of a person that had an L99 that just added another exhaust & when Dynoed posted 361 HP at the rear wheels.
OK so I have just now executed the fuse pull.
Because after all of the upgrades that I did, I only Dynoed @ 350 HP at the rear wheels.
I expected more.
So I guess I'll get to see what happens in the morning......

[PQ]

Originally Posted by CLEAN

So if my car was built in Oct of '09, should I be good or not good?

You should have got the factory update if you've had it to the dealer lately. If not, then yours is affected. do the fuse pull and take it to your dealer for the flash.

Originally Posted by jabbar

Would I have to do this if the car has 87 octane in it and I will be using 93? After installing a new cold air intake and exhaust?

I am buying an LS3 and it only has 18 mi. on the odometer but I think the dealer has filled it up with 87 gas already :( And I will try to put in the intake and exhaust before hitting 100 miles.

I'd do it to instantly correct, but wait til you have a true tank of 93.

Originally Posted by CamaroSS2010

OK - So I have had my L99 since 6/31/09 - I know for a fact that when I picked it up at the dealer - they put 87 octane in it.
I had read about this fuse pull since it began.
But I was not sure if if my car was affected.
I have had the following mods done to it:
Borla catback exhaust
Rotofab CAI
Dynomax LT Headers w/Hi-flo Cats
and a tune.
I have just read a post (above) of a person that had an L99 that just added another exhaust & when Dynoed posted 361 HP at the rear wheels.
OK so I have just now executed the fuse pull.
Because after all of the upgrades that I did, I only Dynoed @ 350 HP at the rear wheels.
I expected more.
So I guess I'll get to see what happens in the morning......

If you had it tuned, you should be good. As long as the tuner restarted from a fresh default.

[Captain McFunk]

So is there an update out from GM for this now?

[dcoates]

Does this problem occur on the LS3?
if so, is the fix the same?
my LS3 was filled with 87 when i bought it, still haven't run it all the way out.
still runs like a raped ape tho!!!

[Cali_Camaro_SS]

Ok tried reading through the first 4 pages and coulndnt get a good answer.
I have a LS3 and I have a Diablosport tuner and set it on the 91 oct. Tune so am I good? or still gotta do the fuse pull?

[TexasTechZ06]

I may have to try this too!

[SPYDERMAN1]

I wonder if this works with a CAI and a tune? Somebody PM me if you know. Thanks

[destroyerofu2]

Originally Posted by lakers67

With the LS3 you just disconnect your battery!

if you do that dont you have to reprogram the windows

[Edrock]

Shortly after taking possession of my LS3, I ran down the gas, put 93 in, did the fuse pull overnight. Drove the next morning and felt definite improvment in performance. So it does work on the LS3 without having to disconnect the battery (which wipes out radio presets, window indexing, etc.) I do agree that once you do it the first time, you would not need to do it again unless you put less than premium gas in or changed the setup of the car (CAI, Headers, SC, Performance Tune, etc.) in order to force the computer to start the re-learning process immediately instead of waiting for it to do it on its own.

[1stSS]

Will this work if my car has not had any intake mods done, yet i did the muffler delete on the exhaust side.

[Bowtie Guy Z28]

Originally Posted by 1stSS

Will this work if my car has not had any intake mods done, yet i did the muffler delete on the exhaust side.

Yes, but only if you think it's feeling sluggish or if you put less than 91 octane in it. I always put 91 in mine but definately notice when I get some bad gas. You just learn to know your car and know it's running a little sluggish vs phenomenal.

[Scott@Bjorn3D]

Fuse Pull ONLY for about 3 hours to overnight is all that is needed. Works on LS3 and L99. Think I have typed this for the 400th time.

[Edrock]

Originally Posted by 1stSS

Will this work if my car has not had any intake mods done, yet i did the muffler delete on the exhaust side.

It certainly can't hurt anything. If I understood the original "sticky" thread, the L99 computers would adjust timing, fuel/air mixture, etc. down whenever less than premium gas was put in the car...as it is designed to in order to protect the engine. The problem was when premium gas was put in later, the computer was not re-learning like it was supposed to, therefore, did not go back to the higher octane tables/higher performance settings. The fuse pull would force a reset to factory default, i.e., starting off on the higher octane levels going forward with the better fuel. Some say the LS3 was not like this but several, including myself, tried it too and it did make a difference with better/smoother idle and driveability. Seemed to have a little more punch too. Do you have to do this after each mod? Probably not but I'm going to for good measure. Hope this helps.