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vzsv8
August 11th, 2008, 10:38 PM
When I look at the SS logs supplied with EFILIVE, idle is at 0% throttle. So when you lift off the throttle it will drop below the 2% or so required and if everything else is in order we get DFCO.
When I log SAE.TP ( throttle position ) on my ECT equiped VZ it never goes below 6.3% at idle, but the DFCO enable level is set at the same level (around 2% ).
Does this mean that ECT cars don't have DFCO? or
Am I logging the wrong PID?
Thanks, Steve

SSpdDmon
August 12th, 2008, 04:34 AM
When I look at the SS logs supplied with EFILIVE, idle is at 0% throttle. So when you lift off the throttle it will drop below the 2% or so required and if everything else is in order we get DFCO.
When I log SAE.TP ( throttle position ) on my ECT equiped VZ it never goes below 6.3% at idle, but the DFCO enable level is set at the same level (around 2% ).
Does this mean that ECT cars don't have DFCO? or
Am I logging the wrong PID?
Thanks, Steve
I think it refers to absolute TP%. What the PCM commands the *ETC* motor to do in terms of maintaining idle isn't referenced for the spark, DFCO, etc. tables.

vzsv8
August 12th, 2008, 02:32 PM
Correct, I have looked at the logs more carefully and the injector pulse widths do go below idle level. For example:
Idle
Pulse With: 2.976ms

vzsv8
August 12th, 2008, 02:42 PM
Correct, I have looked at the logs more carefully and the injector pulse widths do go below idle level. For example:

Idle: Deceleration:
Pulse With: 2.976ms Pulse width: 1.587ms
Throttle: 5.1% Throttle: 7.1%

The only conclusion is that the idle position is subtracted from the throttle position during deceleration before DFCO calculations are made. The only problem is that there is a 2% difference between my hot idle percentage and my 'foot off' DFCO position. Back to the logging I guess. I hate a unsolved problem.
BTW Thank you EFILIVE for black box logging on V2, an SD card is much smaller than my laptop.
Cheers, Steve

endo
June 23rd, 2009, 09:43 PM
Any more ideas on this....I'm logging absolute throttle position on a 2004 GMC Sierra 5.3L with ECT, and am never seeing TP% go below 6.5 or so. It's 10 or better at idle. Default DFCO throttle enable settings are from below 1% to 7%, so it'll never turn on by default. Tried raising to 15% did see a *tiny* bit but need to raise the MAP enable levels for it to work.

Very new to tuning, thought the TP% PID was supposed to read 0%-100% based on pedal position....looked at a log of a 99 Camaro and it does exactly that.

samh_08
June 29th, 2009, 02:57 PM
Log accelerator pedal position instead for ETC