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

[GMRULZ]

Originally Posted by irpq11

First, your 07' Vette didn't have an L99 in it, but a true LS3. The L99 is new with a different cam and AFM and such. (help me guys if I screwed that up).

Actually, the 07 Vette was the last year for the LS2, LS3 came in the 08. Definetly not an L99 for sure...Lol..

[ls2gto]

Originally Posted by irpq11

Just want to specify that Scott S. in this case is Scott Sherman (Scott@bjorn3d) and NOT Fbodfather.

I'm assuming that the battery backup charge is before the fuses in the line. All I know is that a battery disconect didn't reset the right thing.

First, your 07' Vette didn't have an L99 in it, but a true LS3. The L99 is new with a different cam and AFM and such. (help me guys if I screwed that up)

.

LS3 did not come out until 2008. The 07 Vette still had an LS2.

Okay on the Scott issue- it would be nice to know what Fbodfather has to say about all this though.

[ls2gto]

Originally Posted by Blueclyde

OK. Call me the skeptic of this group but I just pulled my fuses. I have a 50 mile drive tomorrow morning to take the car in for a new axle back system, so I will get a chance to see if there is a difference. I knew my car came from the dealer with a tank of 87 octane (bone heads) so I REALLY babied it until it was gone. I would be surprised if I got into any knock based retard/learn but we will see. I have also put about 4 tanks of 93 octane through it since and still can't understand why this system wouldn't have learned back. I would be ABSOLUTELY SHOCKED if doesn't. That would be a major strategy flaw in the control system that I doubt exists. If I notice a difference I will fall on my sword and tell you all.

This is still a great thread with some very interesting perspectives.

Darn, I was going to challenge you to a race against my G8 but now you've gone and added 100 hp!!

Seriously, now even I am waiting to see what happens since you are more skeptical than most.

[Warr3nc]

Hey guys, I've been trolling for years just reading and learning. But considering I was a GM tech for 7 years I thought I could give a little insight as to how they work on these kind of problems. When a problem like this comes up they get enough calls about problems they'll get test vehicles like Scotts. They'll do their research and for whatever reason they issue what they call an internal PI. The only way the tech's at the dealers find out is to call TAC, which a lot of techs don't do or really despise it. Anyway what you get when TAC gets involved you have seen now. I'm more than willing to bet in the not too distant future GM will issue a public bulletin or PI for the dealer techs stating that for a quick fix (customer satisfaction) to pull the fuses as you've seen. Then follow in the bulletin that engineering is researching the cause and a permanent fix will be reissued in an updated bulletin. IMO that fix will be a PCM update that will probably be issued as a recall like the E85 updates in the Tahoes and Suburbans. Sorry for the length I just wanted to try to help see how GM works (oddly sometimes). But a permanent fix and cause will be issued and found.

[PQ]

Originally Posted by Blueclyde

OK. Call me the skeptic of this group but I just pulled my fuses. I have a 50 mile drive tomorrow morning to take the car in for a new axle back system, so I will get a chance to see if there is a difference. I knew my car came from the dealer with a tank of 87 octane (bone heads) so I REALLY babied it until it was gone. I would be surprised if I got into any knock based retard/learn but we will see. I have also put about 4 tanks of 93 octane through it since and still can't understand why this system wouldn't have learned back. I would be ABSOLUTELY SHOCKED if doesn't. That would be a major strategy flaw in the control system that I doubt exists. If I notice a difference I will fall on my sword and tell you all.

This is still a great thread with some very interesting perspectives.

Surely you can't dispute my video evidence?

Let us know tomorrow what happened.

Originally Posted by GMRULZ

Actually, the 07 Vette was the last year for the LS2, LS3 came in the 08. Definetly not an L99 for sure...Lol..

Originally Posted by ls2gto

LS3 did not come out until 2008. The 07 Vette still had an LS2.

Okay on the Scott issue- it would be nice to know what Fbodfather has to say about all this though.

Originally Posted by Warr3nc

Hey guys, I've been trolling for years just reading and learning. But considering I was a GM tech for 7 years I thought I could give a little insight as to how they work on these kind of problems. When a problem like this comes up they get enough calls about problems they'll get test vehicles like Scotts. They'll do their research and for whatever reason they issue what they call an internal PI. The only way the tech's at the dealers find out is to call TAC, which a lot of techs don't do or really despise it. Anyway what you get when TAC gets involved you have seen now. I'm more than willing to bet in the not too distant future GM will issue a public bulletin or PI for the dealer techs stating that for a quick fix (customer satisfaction) to pull the fuses as you've seen. Then follow in the bulletin that engineering is researching the cause and a permanent fix will be reissued in an updated bulletin. IMO that fix will be a PCM update that will probably be issued as a recall like the E85 updates in the Tahoes and Suburbans. Sorry for the length I just wanted to try to help see how GM works (oddly sometimes). But a permanent fix and cause will be issued and found.

So basically it's truely about what we've been seeing.

[djs]

does this mean that if your on a trip and you stop at a station that perhaps doesn't have premium gas in their premium pump that you would go back to a slow car?

[Lord Grey]

More LS3 anecdotal evidence:

My dealer gave me a full tank of low-octane gas, and I'm now running near the end of the second tank, of premium (only about 500 miles on the car). I was seeing non-steady idling, and the car just didn't feel as peppy as I thought it should be. I pulled the fuses yesterday and left them out for a couple of hours.

Damn!

Idle is now rock-solid. Acceleration definitely picked up. I'm not trying to chirp the tires yet, as I'm still more-or-less breaking it in, but I can tell that the power is there. This was definite a win.

[LAWMAN]

same here,i pulled fuses yesterday from my ls3 and replaced 4-5 hrs. later,it is alot smoother and more responsive,i head out to work around 6 a.m. and the car had seemed very cold natured and i live on the coast,the temp. in the mornings is in mid 70's..and i had been thinking man,what is it gonna be like when it is in the 40's-50's...but this morn.it was a ton smoother,not cold natured feeling,the idle is also a ton better.

[LAWMAN]

i had thought all along that the car was running good except for the idle and start up's first thing in the morns.,but now i know just how bad it was running,...how did someone happen up on the idea of pulling the fuses?....whoever,great job

[PQ]

Originally Posted by djs

does this mean that if your on a trip and you stop at a station that perhaps doesn't have premium gas in their premium pump that you would go back to a slow car?

It would appear so.

Originally Posted by LAWMAN

i had thought all along that the car was running good except for the idle and start up's first thing in the morns.,but now i know just how bad it was running,...how did someone happen up on the idea of pulling the fuses?....whoever,great job

This guy (GMRULZ) mentioned it in a thread.

This guy (Scott@Bjorn3D) saw it and and noted it.

and called this guy (irpq11) who, reluctantly, tried it and WOW. Posted it.

It would have been found out eventually but mine and Scotts were the most noteable 'slow' cars on Camaro5. After the engineers fixed Scotts mine and rpepkas cars were. rpepka sold his for a faster one and it left me, and a few others a little less ........ uhh......... 'Bitchy'? .......about it.

So when I fixed mine with the fuse pull (thanks to GMRULZ, and Scott) and posted the videos and results, it became clear.

So there you go. Or you can; S

[thecamaroguy]

Pulled the two fuses on my LS3 last night...left them out overnight (8 hours+)

Reset my my Average MPG of 21.9 and drove to work.

65 Miles later...Average MPG 25.9...

My car ran great prior to this modification and still runs great.
I didn't really have a chance to hammer down on it, but I didn't notice any huge differences in my drive to work. Other than the nice increase in MPG.

[mlee]

Originally Posted by LAWMAN

same here,i pulled fuses yesterday from my ls3 and replaced 4-5 hrs. later,it is alot smoother and more responsive,i head out to work around 6 a.m. and the car had seemed very cold natured ...but this morn.it was a ton smoother,not cold natured feeling,the idle is also a ton better.

I pretty much knew I was on the right octane table, but had to do it anyway. Just to make sure PQ's car didn't end up faster than mine...

Sooooo last night was the night I pulled the fuses. I didn't really put 2 and 2 together until I read your post. From day one my car had a doggy cold start loading up and such. I just wrote that off to a cold car.

I took off this morning smoooooth as ever. Was expecting a jerk or two and it didn't happen.

[LAWMAN]

sounds like your's was acting the same as mine in the mornings,i had no jerking going on this morning like i have had since day one,

[LAWMAN]

WOW! ...my bad dude,