Fuse pull highly recommended

[STINGER BEE]

Originally Posted by stieger

Disconnecting the battery doesn't work. You have to remove fuses #5 and #20

You say both #5 and #20 has to be removed for the computer to reset to default mode.,how long should I leave the fuses out.
Thanks

[The Stig]

Originally Posted by STINGER BEE

You say both #5 and #20 has to be removed for the computer to reset,how long should I leave the fuses out.
Thanks

No one really knows exactly how long you have to leave the fuses out. I, along with most people, usually leave them out overnight. Just pull them before you go to bed and put them back in when you leave in the morning.

[HDRDTD]

Overnight is how I do it as well.
I just have to remember to leave the hood up to remind myself in the morning that I pulled the fuses.

[The Stig]

Originally Posted by HDRDTD

Overnight is how I do it as well.
I just have to remember to leave the hood up to remind myself in the morning that I pulled the fuses.

Smart. I've definitely tried to start Kaylee with the fuses out.

[HDRDTD]

In the morning, before you're fully awake and haven't had time to drink the coffee yet is NOT the best time to wonder why your car won't start.
(I'm assuming it won't start with the fuses pulled)

[PQ]

Originally Posted by BAD ZL1

I am convinced that I should pull the fuses, but can anyone of you, ANYONE...show on a diagram that this car really has a back up battery? If it does, it must be the size of a watch battery....waiting guys...

I have looked and looked and looked. At diagrams and under my car.

I am not good at electronics so I am not sure on the diagram. There appears to be but could just be a junction of some type. Can't remember where I found the diagram but it was using Google.

Originally Posted by ZO6 Bryan

Been researching this a bit and apparently the e67 ecm doesn't just switch to the low octane table. It constantly blending the two tables based on conditions and presence of knock. Using 93 octane should keep you in the 100% use of the high octane table.

From HPTuners forum

quote
E38 / E67 use a percent spark bias approach. With quality fuel you may see 100% High octane spark, and obviously 0% Low octane spark table.

A good tune will run very close to this.

If you are overly aggressive with the High octane spark values, you may see a bias begin to occur - 90% High octane table and 10% Low octane table, etc.

E38 / E67 don't simply run off the High or Low octane spark tables - they continuously blend these values for the best spark per given situation.

And

quote

the ECM interpolates between the high octane and low octane all the time based on the Knock Learn Factor. You can log this in the scanner.

This is why we have recommended pulling the fuses after doing a GM recommended break in of the new Camaro. To reset that 'learning curve' after 1500 miles of wimpy driving.

As far as there not being a set table of high and low that would make sense as to why GM hasn't 'fixed' the problem. Because there IS no problem in that case. But I'm not sure why my car would have EVER 'blended' so low as it did. I always drove my car like I stole it and yet picked up .8 secs immediately after the fuse pull. And I mean .8 seconds after well over 100 runs. Very first run after the fuse pull was .5 faster than the very fastest I had ever run before that.

[STINGER BEE]

Originally Posted by stieger

No one really knows exactly how long you have to leave the fuses out. I, along with most people, usually leave them out overnight. Just pull them before you go to bed and put them back in when you leave in the morning.

Is their a picture in the forums indicating which fuse is #5 and which one is #20.

[Silverguardrail]

I did the fuse pull on my ZL1 (same as my 2010 SS) and it's very noticeable to me.
Glad I did it, more Permagrin

[PQ]

Originally Posted by STINGER BEE

Is their a picture in the forums indicating which fuse is #5 and which one is #20.

[The Stig]

Originally Posted by STINGER BEE

Is their a picture in the forums indicating which fuse is #5 and which one is #20.

Apex Chase posted a pic a page or so back. The inside of the fuse box cover also has a key telling you what numbers each is.

[STINGER BEE]

Thanks Gents,appreciate it very much

[ZO6 Bryan]

Originally Posted by PQ

I have looked and looked and looked. At diagrams and under my car.

I am not good at electronics so I am not sure on the diagram. There appears to be but could just be a junction of some type. Can't remember where I found the diagram but it was using Google.
This is why we have recommended pulling the fuses after doing a GM recommended break in of the new Camaro. To reset that 'learning curve' after 1500 miles of wimpy driving.

As far as there not being a set table of high and low that would make sense as to why GM hasn't 'fixed' the problem. Because there IS no problem in that case. But I'm not sure why my car would have EVER 'blended' so low as it did. I always drove my car like I stole it and yet picked up .8 secs immediately after the fuse pull. And I mean .8 seconds after well over 100 runs. Very first run after the fuse pull was .5 faster than the very fastest I had ever run before that.

Further reading on the tuning boards I found that the ECM returns to the high octane table 10X slower than it moved to the low octane table. Hence why people feel stuck in low octane table. So it will return to high octane ign advance timing eventually, but it is alot quicker to pull the fuses. In the scanner you can read the "Knock Learn Factor" This KLF reads between 0.00 to 1.00 . The closer the KLF is to 1.00 the more the high octane table is used. As KLF approachs 0.00 the low octane table is referenced. So if you simply scan your ECM and the KLF is something like 0.20 then you should put good fuel in it and pull the fuses and it should return to 1.00 KLF. If KLF is say 0.90 then your car is running as it should.

BTW all this can be fixed in a tune by setting the calibration to return to the high octane table faster.

[OldScoolCamaro]

Originally Posted by ZO6 Bryan

Further reading on the tuning boards I found that the ECM returns to the high octane table 10X slower than it moved to the low octane table. Hence why people feel stuck in low octane table. So it will return to high octane ign advance timing eventually, but it is alot quicker to pull the fuses. In the scanner you can read the "Knock Learn Factor" This KLF reads between 0.00 to 1.00 . The closer the KLF is to 1.00 the more the high octane table is used. As KLF approachs 0.00 the low octane table is referenced. So if you simply scan your ECM and the KLF is something like 0.20 then you should put good fuel in it and pull the fuses and it should return to 1.00 KLF. If KLF is say 0.90 then your car is running as it should.

Good info Bryan! ...appreciate it much...

[PQ]

Originally Posted by ZO6 Bryan

Further reading on the tuning boards I found that the ECM returns to the high octane table 10X slower than it moved to the low octane table. Hence why people feel stuck in low octane table. So it will return to high octane ign advance timing eventually, but it is alot quicker to pull the fuses. In the scanner you can read the "Knock Learn Factor" This KLF reads between 0.00 to 1.00 . The closer the KLF is to 1.00 the more the high octane table is used. As KLF approachs 0.00 the low octane table is referenced. So if you simply scan your ECM and the KLF is something like 0.20 then you should put good fuel in it and pull the fuses and it should return to 1.00 KLF. If KLF is say 0.90 then your car is running as it should.

BTW all this can be fixed in a tune by setting the calibration to return to the high octane table faster.

Thank you. Good stuff.

I really wish we could get some tuners in on this for info.

Originally Posted by OldScoolCamaro

Good info Bryan! ...appreciate it much...