DFCO cutting out too soon

[Wolfie]

I'm sure that I am missing something.
DFCO is cutting out way too soon.
When doing a coast down from 60+ it cuts out around 40.
It is not coming near the map or rpm settings.
What else would controll this?
Wolfie

[dfe1]

B3314 is the vehicle speed enable table. What values are in it?

[TAQuickness]

+1.

[Wolfie]

I guess I should havew gave more information, but I was 1000 (am) miles from home
and "borrowing" a wifi connection, so I was in a bit of a hurry.

----
Vehicle speed must remain above {B3314} "(not available in this operating system)"-this value to enable DFCO.

throttle enable
400 0.996094
800 1.992188
1200 3.007813
1600 3.964844
2000 4.726563
2400 4.980469
2800 5
3200 5.078125
3600 5.78125
4000 7.519531
4400 8.945313
4800 10
5200 10
5600 10
6000 10
6400 10
6800 10
7200 10
7600 10
8000 10


dfco rpm

1000 650


dfco map

60 25.996094 30.996094
70 26.992188 31.992188
80 28.007813 33.007813
90 29.003906 34.003906
100 30 35

[Wolfie]

burp....
Anyone?

[dfe1]

burp....
Anyone?
After you excuse yourself, post your tun file so we can get a better handle on the problem.

[Wolfie]

Ahhh ok, but it was the dog who burped...
The OEM and the changed files are here...
http://www.wolf-pa.us/EFILive_Stuff/
I wasn't sure how to post them in the forum, so I just stuck them on my site.
Thanks...

[dfe1]

The problem appears to be there's no B3314 table in your tun file, but there is a vehicle speed hysterisis entry (B3315). I've PMd Ross to see if he can revise the calibration file to include B3314.

[Wolfie]

I actually figured it was that, but I'm too new at this to have said so.
Thanks for looking at them.
I was looking closely while driving, and it seems definitely to be speed related.
In 4th it cuts just as the van crosses 45MPH, and
in 3rd it cuts just as it crosses 33MPH.

By the way, the vehicle is a
2007 Chevy Express 2500 Van, liter, LQ4, E480
Ed

[GMPX]

Hi Guys,

Yeah sorry, it appears to have been left out, I'll check it out.

Cheers,
Ross

[Wolfie]

Does this make any difference on what you are checling out?
I had a cam & lifters wear out after only 97,000 miles on the 9 month
old van, but while it was being fixed under warranty (imagane that!),
I had them reflash it with the updated os... details follow...

12613248 000076F2
New software with diagnostic enhancement for DTC P2108. Replaces 12597120 CVN 00005B34


02-2008
VIN 1GCGG29U671152607
Engine 6.0L
Transmission 4L80E
PCM flash 1Mb
Operating System 12613248
Calibration 12597116
OS ID AK
Cal ID
BCC YKYW
OS Level
Cal Level
Cal file name 12613248.cal
Cal file version 7.91
Cal file date October 22, 2007
Operating System 12613248 $6E88
Engine Calibration 12598851 $7A39
Engine Diagnostics 12598867 $DE72
Transmission Calibration 12598880 $5BBF
Transmission Diagnostics 12599415 $C31D
Fuel System 12598889 $E6D6
System 12598895 $0799
Speedometer 12598909 $9262


02-2007
VIN 1GCGG29U671152607
Engine 6.0L
Transmission 4L80E
PCM flash 1Mb
Operating System 12597120
Calibration 12597116
OS ID AJ
Cal ID
BCC YKYW
OS Level
Cal Level
Cal file name 12597120.cal
Cal file version 7.91
Cal file date October 22, 2007
Operating System 12597120 $C705
Engine Calibration 12598851 $7A39
Engine Diagnostics 12598867 $DE72
Transmission Calibration 12598880 $5BBF
Transmission Diagnostics 12599415 $C31D
Fuel System 12598889 $E6D6
System 12598895 $0799
Speedometer 12598909 $9262

[Wolfie]

Anything yet?

[GMPX]

Well, GM changed the Speed disable to a single calibration, but the bad news is it is factory set to about 20MPH.
There must be something else stopping it. Normally they are calibrated to enable / disable DFCO based on MAP as the primary factor.
For example on an engine with a modified cam you would need to raise the MAP enable / disable values as it might not see MAP down near the 20 kPa

Cheers,
Ross

[Wolfie]

OK, but as I stated above I made all of the available changes and it
cut out out way too soon.

[cmitchell17]

Mine does this to it cuts out at about 45.

[Wolfie]

same here, there has got to be a reason for that!