Just got back from my 10K service during which my 02 S got version 39.1 software. All is great, actually I noticed the MPG is flat out amazing (I'm in Austin, the dealership is in San Antonio). The same thing happened when they flashed it to version 38, outstanding MPG, greatly reduced stumble and almost no sign of yo-yo. But as the subsequent weeks rolled by, my MPG settled back down and the stumble and yo-yo reared their ugly heads.
What can we do to keep the adaptive part of the software from relearning it's old BAD habits? I'm kind of heavy with my right foot and I tend to use most of the RPM bandwidth on my daily commutes so I'm not looking in the mirror for any blame. But what gives? I get the car back from the dealer and it's great, why can't it just stay that way?
I read a thread a while back that gave instructions to "reset" the software by turning the key to the second position and holding the trip odometer untill everything starts flashing. Then you "scroll" through the options untill something or another...But from what I understand this method doesn't clear out the adaptive portion of the software, only the dealership can do that. Can't the guys at MTH or something shut down that part of the software? Has anyone actually seen their car improve through the adaptive cycle? My guess is, my car just runs a bunch richer as time goes on.
Just wondering if I'm the od guy out here, or if others have experienced this same pattern?

 

Usually [grain of salt here] the car will learn to get better fuel economy as time goes by, but then again we are talking about the coughstupidcough Siemens EMS2000, so just about nothing is certain.

 

when i got flashed v38 from v37, i did not notice a change in MPG

o well, maybe v39,40,41,42,43,44,45,46,or 47 will make it better

 

Honestly after getting the V39.1 recall flash, I haven't noticed any significant differences in the way the car drives. Fuel consumption seems the same to me as when I had V36 in the Siemens ECU.

 

Des Moines to Kansas City 26 MPG after flash KC to DSM 30.25MPG