After Extensive E38 L92 Tuning, Gas mileage horrible and no power....

[raceghost]

Just because it took 3 degrees higher and had no knock doesnt mean thats the correct timing. 99% of the vehicles I re-tune from other shops I make more power or the same same power and I run less timing and usually get better fuel mileage. To much timing will make it lose power which will make it get worse fuel mileage also.

I agree, there is such a thing as the sweet spot.

Just put it in MAF only and tune it and be done. I think your over thinking this way to much, people tune with efi live everyday, efi live is not holding you back. I would start over with the stock file and start re-tuning in MAF only and be done in a day.

At first glance, I would tend to disagree, and think Lazy! However, if your saying start with maf, and then finish the SD portion, then ok. But if you are suggesting running on Maf only, then I think that is the lazy way of tuning IMHO.

have a read of the Virtual VE Tutorial, it might help making sense of how it works

Yes. When I originally started this post, I was waiting on widebands. I finally got them installed so I can tune using the tutorial. At time of post, we were using the dyno widebands.

Either way, with the glitch I am seeing in the VE tables at the moment with my rom, I cant enter any updated info without the software changing what is in there. Very frustrating.

[raceghost]

Bump for any info or progression the VE table issue.

Also, found a few things wrong with the truck,

The guy who put the JBA headers on broke (3) of the Magna Core Spark Plug wires and repaired them, found this hidden when I changed the plugs yesterday. They pulled right off, and were barely hanging on, and you could see where they had attempted repair.
New wires in.

Lowered the timing another 2 degrees, picked up a full (1) MPG on the tell tell info center without resetting the trims or learned data... this is driving around town...

MAP sensor was shot as well, replaced that with new too.

Also, the right manifold compression connector was a little off center, and a small exhaust leak was found.

All issues fixed.

But, to get back out there and log and tune the VE tables and MAF again, I need to be able to save the data in the VE tables.

Thanks in advance

[joecar]

[QUOTE=raceghost;255011]Bump for any info or progression the VE table issue.
/quote]
I'm still playing with this.

MAP sensor was shot as well, replaced that with new too.

What did you see that indicated broken MAP sensor...?

Also, the right manifold compression connector was a little off center

I'm not sure which connector you mean here.

[joecar]

Try the stock tune as sanity check, log the following pids (from the stock tune) using V7 (meaning V7.5) and post here:

SAE.RPM
SAE.ECT
SAE.IAT
SAE.MAF
SAE.MAP
SAE.LAMBDA
SAE.LONGFT1/2
SAE.SHRTFT1/2
GM.HO2Sx1
GM.MAFFREQ
GM.SPARKADV
GM.KR
GM.ETCTP


( I'm on 2.5 jobs at present, so my replies will take a bit longer )

[joecar]

Remind me again what the first 2 tunes are:

• BossHog.Mario.Tune.4.23.21.BaseForSkunkworksV3.ctz
• Skunkworks.V2.BossHog.Base.IdleSpeed.EPRevLimits.T orqueControl.2009CoilDwell.DynoTimingCustomSmo.ctz
• BossHog.Stock.ECM.ctz

[joecar]

If you're running catalysts, why did your tuner disable cat protection (should leave it enabled, it will kick in when needed)...?

There are very many changes in the tune file, imho many of those are not needed and some may be questionable (changes to spark dwell and known detection).

[raceghost]

What did you see that indicated broken MAP sensor...?

Verified by part number it was a 2007 MAP sensor. 170K miles on it, clogged with oil, and was reading off. Decided to clean it, and check with logs, then tested with new with logs, and New read better...

Also, the right manifold compression connector was a little off center

The right side, passenger side exhaust manifold to downpipe connector is a compression style, 3 bolts with bell on one side, and cup on other. If you dont have it set right, it can leave an air gap for exhaust to escape, or tighten 2 of the bolts tighter than the third, and it will yield the same... which it was.

Try the stock tune as sanity check, log the following pids (from the stock tune) using V7 (meaning V7.5) and post here:

SAE.RPM
SAE.ECT
SAE.IAT
SAE.MAF
SAE.MAP
SAE.LAMBDA
SAE.LONGFT1/2
SAE.SHRTFT1/2
GM.HO2Sx1
GM.MAFFREQ
GM.SPARKADV
GM.KR
GM.ETCTP

I will when I get back to town. Currently on road trip with vehicle, averaging 17 MPG on the freeway at 80 mph. Worthy to note, my stock rom, Trims are 15% off, as in Lean, constantly adding 15-17% fuel. Throws lean codes after about 100 miles of driving.

Remind me again what the first 2 tunes are:

First rom with "Mario" in name is the latest Dyno tune, with VE adjusted, as well as other adjustments.

"Skunkworks.V2..." was the previous tune, missing VE adjustments, or no VE adjustments.

I have made several adjustments to the latest dyno tune in the last few weeks(which was file 1 with Mario in the name). I can attach this file as well. The only thing I can not adjust is my VE tables. Like I said, they keep auto changing.

If you're running catalysts, why did your tuner disable cat protection (should leave it enabled, it will kick in when needed)...?

Not sure, but good catch. I'll turn it back on.

There are very many changes in the tune file, imho many of those are not needed and some may be questionable (changes to spark dwell and known detection).

Spark Dwell for example is direct form a 2009 Cadillac Escalade EXT, same truck, 2 years newer, I also have Aftermarket coils.
Torque Tables are 2009 torque tables which we have spoken about over in another thread. Have not noticed in negatives with them.
I have also adjusted the Dynamics tables, and turned it on. 2007 is shut off or maxed out so it never comes on or plays any part. I used 2009 Table data as well on it, and it works beautifully in logs so far as well.

I have Dual AFR gauges and watch them constantly as well.

Like I said, in general, GM rushed these trucks to Market in 2006~2008, remember we bailed GM out, again, in 2008... There financial troubles did not just happen over night... and some of the cause of these troubles, was shitty tuning and warranty issue caused by it.

But I am interested in any education or comments, or suggestions relating to what your seeing when making the above comment. Always down to learn.

Thanks in advance,