Tuning Help Please

[totalengine]

2005 GMC 6.0L with LS9 Cam and Supercharger. only 4psi of boost.
i have upgraded to a 2 bar speed density tune.

the truck from 3,000 rpm to 4.000 rpm will run at a AFR of 13.8-15 no matter what i do. i have maxed out the areas in the maf and ve and have added way to much fuel in the power enrichment and nothing helps. As soon as it hits 4,000 rpm the afr drops down to 11.5 ish and is fine after that.

any one have any ideas?

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Attachment 37431

[The Shop Inc]

Max out your Enrichment Ramp-in??

[totalengine]

yeah put it at 4.000 and didnt help. thats what its on now

[edcmat-l1]

I've seen issues like this when trying to run a MAF with a SD COS. Turn the MAF off and dal in the VE.

PS, it's in PE when it's lean, so it's not the enrichment ramp time.

[mowton]

Not that familiar with Custom OS's but I would recommend reading the tutorial in the help file, fix your scan cfg (remove MAF and MAP (SAE) accordingly from your scan chart , import the applicable histograms for the 2 Bar Speed Density OS, put the VE back to where you had before you "spiked it, disable STFT open loop control and try again. As Ed above said, it is in PE and commanding the 11.5, but the PCM is not providing the necessary fuel for some reason. I am trying to remove any "closed loop: controls that might interfere.

It seems the 4K point is the magical Hogh RPM Enable but not sure if that operates the same as in the OEM OS.

Hope this helps

Ed M

[totalengine]

well i tried to turn off the MAF and from what i can tell it should be running in SD all the time. But that still didn't fix my problem. unless i didn't change enough table in the tune to completely turn off the MAF.

Attachment 37462

Attachment 37463

[ak2007r6]

Your PE Throttle/Pedal is set at 55% for both Hot and cold. I would try lowering that down and seeing how it reacts for you.

[totalengine]

ok i lowered PE Throttle/Pedal to 36% from 2,800 to 4,000 and 26 from 4,000 up and still no change

[ak2007r6]

I went back and looked at your log and you can see at frame 91 that it enters PE and is commanding 11.5 but nothing changes. Even when you go WOT at frame 124 nothing changes....

There has to be a modifier table affecting it somewhere...

[totalengine]

I am hoping some one has ran into this before but i cant find anything online.
Found one thread where some one said to set everything under PE Enable to 0 and that had no effect either.

here is another log for any one to look at

Attachment 37464

[totalengine]

What does not make since is the truck ran fine until i upgraded to this OS and the only reason i did it is because it was maxing out the MAP sensor. is it possible that its some thing that happened when i upgraded?

some more info: this truck came to my shop already "Tuned" but after the motor melted a piston he put a 6.0L in it and brought it to me.

Here is a Stock 2005 5.3 tune that i compared his truck with before i started tuning and before i converted to the 2 bar MAP speed Density OS

Attachment 37471

[edcmat-l1]

You're still not in SD. Set the MAF codes to 0 or 1. MIL on first or second fail. You can't set them to no error reported. Won't work.

[totalengine]

You're still not in SD. Set the MAF codes to 0 or 1. MIL on first or second fail. You can't set them to no error reported. Won't work.

Interesting, that's worth running back up the the shop to try. Ill post results.
Btw thank you guys for helping

[totalengine]

Well......... it looks like that fixed it
the AFR dropped down to 12.0 and there was about 2%-7% error across the board.

I only made 2 runs on the dyno and only went up to 4,500 RPM so I will try to dial it in in the morning. I will let you guys know if everything works out good.
Thanks Again!

[ak2007r6]

Nice!

[mowton]

You're still not in SD. Set the MAF codes to 0 or 1. MIL on first or second fail. You can't set them to no error reported. Won't work.

interesting...a Speed Density COS requires failing the MAF like the OEM OS