ppsi

I had an Edge EZ and VA duration on my truck and was getting almost 19mpg by calculator. I brought the truck in for the tranny line TSB and removed all the goodies. Since then my mileage is about 16.5 at best. I posted this before but have some additional input/info. First off the tech I deal with couldn't care less what I have on the truck and asked why I took off all the boxes. Anyway I spoke-w-him about the mileage and he suggested that the boxes may have changed some values in the ECM from the original configuration and I should bring the truck in and he would reset the ECM to "as purchased". Can these boxes actually change the programming of the ECM? or just manipulate the outputs?
Also in reading all the posts it is incredible the variation I see in similar trucks. It may not be "apples to apples" in comparison but it seems some are getting twice the ,ileage than others
?

I have a light foot except when needed and 16.5 suck IMO for an empty 2X4 QC-w-a bed cover.

thejeepdude

So, um, did you put the boxes back on and see if the mileage comes back up? Or are you saying you did put the boxes back on and the mileage stayed at 16.5? If you haven't put the boxes back on, and you were getting a calculated 19.5 with them, then it seems you should put them back on!

ppsi

Well this is the chain of events:
Bought truck 12-31-04 - mileage 17-18
1500 miles added Edge EZ - mileage high 18
added VA Duration at 6k Miles mileage still high 18 to 20+ on highway
at 10 took off all boxes for Tranny TSB - Mileage mid 16
Put VA back on at 1/2 a tank and mileage stayed mid 16.
Just today I put the Edge EZ on setting #3 back on.
The power-w-Edge and VA on 2 is generous but of course EGT's are oput of control.
I honestly think the power was better prior to removing the boxes and then re-installing them. For some reason I think the truck-w-"fresh" programming did better-w-the boxes then after removing and re-installing almost as if the boxes messed-w-the ECM while they were on.
ANY ideas are appreciated

thejeepdude

Well, I'm not sure about our ECM, but I some ECM's tailor themselves to your driving style over time and environmental conditions and such. It could be that having the boxes on there, since the ECM isn't reading actual values but what the boxes are telling it, that once you removed the boxes, the ECM thinks "whoa, normally at this throttle position, boost is x, and fuel is x, but now fuel is x and boost is x and speed isn't the same, and it just got confused and is dumping more fuel later in the cycle or something <??>. Perhaps after driving it for a while with the boxes on, it will re-learn things. Or maybe your friend was right, and the ECM needs to be reset to "factory defaults". I wonder if leaving the battery disconnected for a period of time might reset things... just a theory, but I hope you get it figured out. Keep us posted if you do!

ppsi

Disconnecting th e battery is a great idea. I will do this asap. Again, I have reconneected the VA and EZ and the power is great but still seems a bit lacking as compared to before I removed them. There must be a tech-w-the knowledge about how these ECM's work/learn that can shed some light.