Doc99SS

iTrader: (2)

I have copied the high octane timing table over to the low octane.
I have made the secondary VE table same as main VE table. This main VE table is the same one from my factory '99 table.

I flashed this new program onto the PCM. Disconnected the MAF sensor. Drive the car around and data logged.
FTC 6 and 7 were -12.5% -12.5%,,,
FTC 10 @ -9.4% -11.7%,,, FTC 11 was at -6.2% -8.6%, and
idle FTC 19 at -8.6% -8.6%... With these LTFTs, my WB is hovering arounf 14.7...

So I come back in and edit the program. I figure the PCM is taking fuel out, therefore the MAP values are too high. I multiply areas 6 and 7 of both VE table by 87.5% FTC area 10 by 90.0% and FTC 11 area by 92.0%, and I am idling in area ftc 8 on the VE tables, therefore I multiply this area by 93.0%.

I flash this new program onto the PCM, start the car up and go for a drive. To my surprise, the LTFTs have not changed, FTC 6 & 7 is still showing -12.5% and -12.5%, and FTC 19 is still -8.6% -8.6%...

I dont get it !!!!!!!!!!!!! The LTFTs should have been near 0.0% +- 3.0%

Doc

iTrader: (9)

Do you actually have a MAF failure dtc?

Doc99SS

iTrader: (2)

Yes, P0102. That is an interesting question. I know for a fact that I have it now, after the second test drive.

edcmat-l1

iTrader: (10)

Why are you using your long terms? Why not turn them off and use your short terms?
Can you post a tune and a run log?
Why arent you using your histograms/maps to plot your VE changes?

Viper

iTrader: (6)

And reset the fuel trims in the VCM controls after you turn off LTFT learning in the editor.

Doc99SS

iTrader: (2)

Thank you for the responses. As some of you might know, I use LS1Edit, I have had this programmer since 2001, however, I do have the lastest upgrade ver 1.54.. And I know that this is mainly an HPTuning board. So, concerning the histograms and LTFTs, I will have to modify the VE tables by directly editing the tables. I want to avoid a battle between the programming software. The same strategy that works for one, should work for all, as long as they are full editers.

I have read many threads on this board and they have the same advise, get the LTFTs at max +- 10%. Then work with the STFTs. One article was very interesting and well written "How to Tune Your VE Tables Using Fuel Trims". I do not have the LTFTs under control yet. And I dont understand why after making the correct editd to both VE tables, the LTFts have not gone to 0% +- 3%. Its like my changes to the VE tables meant nothing because the LTFTs in both FTC 6 & 7 went to -12.5% pretty fast. This is the root of my question.

And I data log with a version of AutoTap from 2000. So, I probaly can not edit (tune) precisisly in the same manner as others, but I do have the tools to fully edit the PCM program and determine what needs to be changed. Please help me out.

I have made a new scanning file which will data log LTFTs, STFTs, FTC, RPM, MAP, MAF, KR, PWs, O2s. And I have a WB.

Doc99SS

iTrader: (2)

Could I please get some help?

Billf6531

Did you reset your fuel trims after making the corrections?

edcmat-l1

iTrader: (10)

It takes too long using ltft. If you disable them, and just use your short terms, you can see near instantaneous results.
When you reflash with edit, does it flash the calibration only, or does it do a complete rewrite? The reason I ask is if it just flashes the cal, then you'll need to reset the fuel trims. If it does a complete rewrite, I believe that resets them just from full flashing it.

Doc99SS

iTrader: (2)

"Did you reset your fuel trims after making the corrections?" No, however I understand that the LTFTs are set back to 0% during a reflash, as well as, the DTCs. I might be wrong here, but again, the LTFTs, if they started out at -12.5%, they should have relearned back toward 0% with my changes. My datalog shows that they did start out at 0% and relearned back to -12.5%. Very confusing to me.

I believe that LS1Edit does a complete reflash, therefore the LTFTs are set back to 0%.

edcmat-l1: I understand your point about the quickness of the STFTs vs the LTFTs. When the STFTs go out of range for a specific time, the LTFTs get kicked into action. My new file in AutoTap will datalog the STFTs as well as the LTFTs. It seems that FTC 6 and 7 relearn the LTFTs in about one minute or less per FTC driven in. I'm going to do PCM reset, the go out for a new drive with the current programming that should have had the LTFTs near 0%, with the MAF disconnected.

As always, Thank you for the replies.

Doc99SS

iTrader: (2)

I am back from my test drive, started out with all Fuel trims at 0%. after driving about 12 minutes FTCs 6, 7, 10, and 11 fully relearned. FTC 6 and & are still at -12.5% which is the same value even after reducing the part of both VE tables 10%. STFTs would go deeply negative immediately as soon as the PCM got into closed loop, then the LTFTs went negative. After the LTFTs settled into -12.%, the STFTs would bounce around above and below 0%, as expected.

So, it still seems like the first time that I editted the VE tables down by 10% it had no effect.

VH5150

ls1 edit is old school.... it will work but there is much better software out there..

edcmat-l1

iTrader: (10)

Then reduce em again by 10% or so.

Doc99SS

iTrader: (2)

Thats exactly what I did, and then conducted another test drive. The LTFTs are
FTC 6: -7.0% -7.0%
FTC 7: -4.7% -5.5%
FTC 10: -2.3%, -4.7%
FTC 11: +11.7% +14.1% (I dont understand this one, too big of a result change based on previous edits to the program)
Overall some effect now, but FTC 11 is way too positive. FTC 11 had by far the largest response to my changes. I editted another program last nite and called it quits at midnight.

Slowhawk

iTrader: (12)

Do yourself a favor and dump LS1edit.It will be worth your time in $$ to buy HP or EFIlive.Nevermind a hell of alot easier to tune with.

edcmat-l1

iTrader: (10)

I agree. Its worth saving time and headaches to just cough up the dough.

Doc99SS

iTrader: (2)

Explain to me how having HPTuners would have made my first change of 10% down in both VE tables have made a difference to me, and have gotten me a 10% change that i expected in my datalog?

I am after direction and help. There are others who use LS1Edit. Besides, no matter what tuner you use, the approach that is used is most important. And maybe some of us are short of cash or, worse, out of work now, and simply cannot justify an expence like that.

Billf6531

Post the current tune and a log. I have an LS1 Edit viewer left over from the Dark Ages.

Doc99SS

iTrader: (2)

Bill6531, I sent you a PM.

edcmat-l1

iTrader: (10)

Not tryin to knock you for what equipment you're using. And I can understand being strapped. But, you'll never understand just how powerful a tool the other tuners are if you've never used them.
EFIlive and HPtuners both have histograms in their scanners that make dialing in a VE table or MAF table a breeze. Actually, you can set up multiple histograms and plot things like A/F correction in each cell in one histogram, and knock retard in another one.