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View Full Version : CalcVE insanity check... duh?



Wolfie
May 19th, 2010, 09:39 AM
OK, I must be doing something wrong here...
I checked and rechecked my data, and this MAF cal just looks wrong.
(Comparing the logged to the factory tune)
-I think a picture should follow-

WeathermanShawn
May 19th, 2010, 11:47 AM
Wolfie:

MAF units have to be in g/s.

As always a log, or a good screen-shot of the selected PIDS is helpful.

I.E...its always about the units..
Good to see you back..:cheers:

Wolfie
May 19th, 2010, 01:12 PM
I didn't put up a tune or log, because I figured something very basic was wrong with the numbers... I looked and looked but kept missing the "obvious"! That was from a 300 mile log, I will see what happens on the next one.

-Thanks...
--it was a rocky couple weeks, but much better now.
---I had replaced both o2 sensors, then replaced the bosh (plx) sensor,
then developed a small over heating problem... found the fan clutch bad...
then found the radiator completely corroded and seeping from both sides...
damn chevies! I could have bought a new one with all the money in repairs!

joecar
May 19th, 2010, 01:35 PM
Wolfie, post some files.

Wolfie
May 19th, 2010, 01:41 PM
Well... OK...

WeathermanShawn
May 19th, 2010, 01:54 PM
Wolfie:

I am fairly certain the trouble is in the unit conversion..but you never know.

By chance, do you know what the average LTFT and/or LTFTBEN(S) were for your trip? If that data is good, I can usually infer how the MAF Calibration Table should look.

If not, next time you log..do a sanity check after a few miles. I have done the same thing..logged some miles and got something mixed up with a PID or two..:grin:..

Wolfie
May 19th, 2010, 01:58 PM
Here is the log...
It was too big, and EFILive forum wouldn't upload it...
it is here...
http://wolf-pa.us/downloads/

file is Log_Wolfie_cve-ready1.efi

WeathermanShawn
May 19th, 2010, 03:53 PM
Wolfie:

I was mistaken..You did it right. Yes, its a long log..I had to reconfigure my Scan Tool, but I got it. Not sure..but did you actually log 27 channels?

Anyway..good news. Everything logged just fine. Your LTFTBENS are reasonably good..a little positive. Your CALC.VE TABLE looks good (I probably don't understand why your IDLE VE TABLE %'s are so high)..Probably a lot I do not understand about your OS..Why does TPS never go to zero?..Or did I just miss it..or I do not understand your vehicle platform that well?

Wolfie..it looks generally O.K. I am impressed that your CYLAIR and DYNCYLAIR values are very comparable as is..Well here is what I plotted..

WeathermanShawn
May 19th, 2010, 03:56 PM
Your CYLAIR and DYNCYLAIR side by side..Pretty good!

ScarabEpic22
May 19th, 2010, 04:02 PM
Shawn, wolfie has an 06 van so it has ETC. With ETC you will never see 0% TPS except at key off, the throttle position usually sits between 6-10% (or more for modded trucks) depending on conditions (A/C, cold start, etc).

It confused me at first too, both of my trucks have ETC and when I was first learning to tune I was super confused why I could never get 0% TPS.

WeathermanShawn
May 19th, 2010, 04:11 PM
Thanks Erik:

I thought I was seeing things..their is so much I do not know about differing vehicles and OS. Thats a good one.. it really threw me.

Here is Wolfies 'original' VE Table and the CALC.VE Table. Like I said, I do not know if I understand why the 'Idle' CALC.VE are higher. I assume it is because his MAF Freq and airflow are simply higher there. I am used to looking at high-overlap cams at Idle..

Well, food for thought..Thanks again for the explanation, Erik. Makes more sense now..:cheers:..

Wolfie..your CALC VE values are generally higher because your MAF Airflow is applying the LTFTBEN correction (correctly). If you filter, cut, paste etc..via the Tutorial..I think you have successfully done it. I need to ponder that 800 RPM column..:confused:

WeathermanShawn
May 19th, 2010, 04:28 PM
Wolfie:

Sorry about the multiple posts..I keep thinking of new things.:).

Is your normal Idle MAP ~35 kPa? If it is, then your Idle CALC.VE Table numbers look good. Perhaps it might have tried to stall a few times? That can occasionally throw both the MAF and MAP higher, before it goes back to normal Idle.

Perhaps you can manually work that 800 RPM Row above 40-45 kPa..you don't want the VE Values to be artificially high..cause if you are stalling..no need to have too much airflow, and hence risk over fueling and bogging..

Wolfie
May 20th, 2010, 12:06 AM
No, Idle is "perfect", not trying to stall at all.
My original wonderment was why the maf seemed to be on a curve when
the original was a slope.
Logged 23 pids, but I do see it was 26 channels (I stuck an extra one in there for the 24/27 so I would remember to look at the cl mode)


Thanks for looking! I wasn't sure I was on the right track.

joecar
May 20th, 2010, 04:10 AM
The MAF is supposed to look like an ever increasing curve (exponential looking).

Wolfie
May 20th, 2010, 05:53 AM
Here is what I found...

1.On decel, the numbers on the maf calc go nuts, I believe it is because the plate is still open 12%. So I made another log filter to disreguard all frames that are greater than 1 mph and below or equal to 12%.

2. You DO NOT need to log 300+ miles to get a good reading!

3. Read the tutorial!, then read it again, and again, and again!

BUT... After getting everything sorted out,
when I do a paste and multiply with the maf...
the numbers do not make sense.

I posted another SHORTER log.

WeathermanShawn
May 20th, 2010, 07:14 AM
Wolfie:

Just a double-check. After your first log (300 miles) did you apply the LTFTBENS (MAF Calibration Table) back to your tune?

The reason I ask, is that this log shows the same LTFTBEN correction as the last. The LTFTEBNS should have went to near zero.:confused:..

It is possible that an ETC-controlled vehicle may have extra challenges in filtering our various TPS %'s to get an accurate picture. But, the bottom line is that it is the MAF Airflow numbers (and LTFTBENS) that drive the equation. As long as MAF Airflow goes down when decelerating..:confused:

We will keep checking. The ETC angle is new..but I think we can figure it out..:)

Wolfie
May 20th, 2010, 03:43 PM
No, I didn't make any changes, because when I did the paste and multiply, the numbers went nuts. They were not even close to anything normal.

WeathermanShawn
May 20th, 2010, 04:07 PM
Wolfie:

Best I can tell is that you do not have enough digits selected for your LTFTBENS. I.E. In the Scan Tool..Map Properties..Precision (3).

When I load up your MAF Calibration Table, I get numbers like 1.054 for your LTFTBEN. You have 5.4..Its missing the 1.0 Integer and decimal in front.

Can someone look please it over. I probably am not explaining it properly. I could easily modify your tune to show the correct numbers..but best if you can get this straightened out. With the BEN number in front of your data..it works perfectly..

Thanks for any help..

joecar
May 20th, 2010, 09:05 PM
Wolfie,

Ah, that's it, what Shawn said, you have to use LTFTBEN rather than LTFT in your map.

Wolfie
May 21st, 2010, 09:59 AM
Duh... again... I had the wrong pid selected...
Thanks Shawn and Joe!!!