** ECM TRUNK FUSE PULL **

[IndeedSS1]

I decided to post these last scans with the 87 octane because of the increased numbers in the Knock Learn Factor table. This was after about 250 miles with the 87 octane and right before I had to get to the gas station for a nice fill up with 93.

[IndeedSS1]

93 octane back in the tank and scans started after about 30 miles. I think we can agree that the knock learn factor is starting to shift back to the high octane table. From what I saw with the 87 portion, it takes a while to learn, like the fuel trims do. On my car this seems to be 100+ miles. Anyway, I'm going to give it that 100 miles before posting the final "return to 93" scans.

For those that have not seen the TSB for the fuse pull, it specifically states that it is for the L99 with AFM. My car is the LS3.

[IndeedSS1]

Went for a long Sunday afternoon drive, hoping to allow the learning to complete. It dose take several counts in each cell for the learn to settle in. As you guys can see from the below scans the knock learn factor has nearly completed after returning to 93 octane. I'll do one last post comparing only the KLF.

[IndeedSS1]

Here is how the knock learn factor works on the LS3. First is 93 octane. Second is after running the tank low and driving about 250 miles on 87 octane. Last is after running the 87 octane out and going about 100 miles on 93 octane. Based on these results, I have major doubts about the fuse pull as it applies to the LS3.

[PQ]

Too bad we can't test an L99.

[IndeedSS1]

Originally Posted by PQ

Too bad we can't test an L99.

I agree.

[MrWray]

so the fuse pull is for fuse #5 and fuse #20 under the hood,correct?

and what about 91 octane? where i live there are very few stations around that carry 93

[IndeedSS1]

Originally Posted by MrWray

so the fuse pull is for fuse #5 and fuse #20 under the hood,correct?

and what about 91 octane? where i live there are very few stations around that carry 93

If you have an LS3 it appears that a fuse pull does nothing unless you were to do it as soon as 93 was reintroduced to speed up the process by 100 miles.

If you have the L99 then the fuses are 13 and 20 with 13 being in the trunk. 13 is the B+ voltage for the PCM.

[1JEWLDSSRS]

Originally Posted by IndeedSS1

If you have an LS3 it appears that a fuse pull does nothing unless you were to do it as soon as 93 was reintroduced to speed up the process by 100 miles.

If you have the L99 then the fuses are 13 and 20 with 13 being in the trunk. 13 is the B+ voltage for the PCM.

I have just seen this thread and I have an L99 and have been pulling the 5&20 fuses once in a while, but this is the first I have heard about fuse#13?? Where in the trunk is this fuse located as I had no idea there were any fuses in the trunk. Thanks, Oh and I do only use 93 Sunoco in my car, but sometimes I have to put some other 93 in it and seems to affect the performance. Thanks for all your info.

[IndeedSS1]

Originally Posted by 1JEWLDSSRS

I have just seen this thread and I have an L99 and have been pulling the 5&20 fuses once in a while, but this is the first I have heard about fuse#13?? Where in the trunk is this fuse located as I had no idea there were any fuses in the trunk. Thanks, Oh and I do only use 93 Sunoco in my car, but sometimes I have to put some other 93 in it and seems to affect the performance. Thanks for all your info.

Near as I can tell 5 and 20 was picked simply because that was the two fuses under the hood that said PCM on them. Fuse 13 and 20 was mentioned in GM TSB. After I looked at the diagrams it was easy to see why 13 would be one to pull. All of this fuse pull stuff was delved into by others. I was simply curious and want to see what was going on, if anything.

If you look at the fuse pull sticky at the top of this sub-forum on about page 91 and beginning with post #2252. PQ was nice enough to show where fuse 13 is located and how to get to it.

Here is the TSB http://www.camaro5.com/forums/showpo...postcount=1261

[1JEWLDSSRS]

Originally Posted by IndeedSS1

Near as I can tell 5 and 20 was picked simply because that was the two fuses under the hood that said PCM on them. Fuse 13 and 20 was mentioned in GM TSB. After I looked at the diagrams it was easy to see why 13 would be one to pull. All of this fuse pull stuff was delved into by others. I was simply curious and want to see what was going on, if anything.

If you look at the fuse pull sticky at the top of this sub-forum on about page 91 and beginning with post #2252. PQ was nice enough to show where fuse 13 is located and how to get to it.

Here is the TSB http://www.camaro5.com/forums/showpo...postcount=1261

Very good, thanks so much.

[IndeedSS1]

Originally Posted by 1JEWLDSSRS

Very good, thanks so much.

You are welcome.

I don't suppose you know anyone with HP tuners that can do a before and after fuse pull scan? We would really like to see if the L99 is able to learn back to the high octane timing like the LS3.

[hapisok]

a little something i found posted by 10_SS on HP Tuners forum, maybe this might help clear some things up:

http://www.hptuners.com/forum/showthread.php?t=40938

Not sure if this is 100% what you want, but the way I understand it is this as I have a log with some knock that shows the knock learn factor incrementing, but as soon as the knock quit's, the knock learn factor goes back to 0.00.

knock Lean of 0.00 = 100% reading from the high octane table.

As the PCM see's knock, it will increment the knock learn factor, which makes it start reading from the low octane table.

What I am unsure of, is how high the knock learn will go, and what makes it stick high, making the PCM lock to the low octane table.

I also heard, once the knock learn factor is high enough, or locked into the low octane table, the knock lean factor wont reset until the gas tank runs low, then is refilled, then knock learn factor resets and the high octane table starts again.

Pulling the battery simply resets the knock learn factor, allowing timing back to the high octane table.

The resetting of the knock learn/low octane table when you refill the gas tank makes sense as once it's detected bad gas, the bad gas will stay bad until you refill.

EDIT: I just looked at your logs, while I dont have the individual cyl. knock learn factor being logged, I do have the "Knock Learn Factor" being logged... and mine only increases when I get actual knock. Your's is bouncing all over the place, like you said but I didnt see any knock in the log.

I have a 2010 Camaro LS3, something tells me we are looking at different parameters.

EDIT AGAIN: Attached my log of Knock Learn in action @ 23738 (and yes, this knock has been noticed during extreme fast WOT... still working on solution other than slowing the Throttle Opening Rates)

[GEEKFREEKSCOTTY]

Originally Posted by IndeedSS1

Near as I can tell 5 and 20 was picked simply because that was the two fuses under the hood that said PCM on them. Fuse 13 and 20 was mentioned in GM TSB. After I looked at the diagrams it was easy to see why 13 would be one to pull. All of this fuse pull stuff was delved into by others. I was simply curious and want to see what was going on, if anything.

If you look at the fuse pull sticky at the top of this sub-forum on about page 91 and beginning with post #2252. PQ was nice enough to show where fuse 13 is located and how to get to it.

Here is the TSB http://www.camaro5.com/forums/showpo...postcount=1261

I noticed that the TSB doesn't say how long to leave the fuses out for? I'm assuming that you are leaving them out for a specific amount of time so that a capacitor has time to discharge?

Or, is the best way to go, to pull the fuses and the positive on the battery, and leave out for about 5 minutes?