Well, another issue that i realized, and it seems i am not the only one, i think i might of found what the issue might be, ever since i got my pcm tuned, i never was able to get my speedo right, even if i tried the calculator, my gauge would never give me the right speed, and even more weird the pcm would see another speed than the one indicated by the gauge, for as long as i can remember i always thought it was my cluster being too slow, anyways, i got a stock pcm with the stock pcm calibrations for my year 2002 trailblazer with 3.73 gears, i even asked some folk here for a stock file just to be sure, well even there with the stock settings my speed would still not be right, the speed between the pcm and the gauge would have a 5 mph diff, and worst of all if i had my pcm flashed with the new settings for my bigger tires, the pcm would still be off by about 4 mph and the gauge by about 6 mph compared to the pcm, so after going to the dealer getting a routine check, i installed the the stock pcm and asked him if he could do a tires size change for me, he was unsure and let me fiddle around with it, there it was tire size change, and my tire size selection was there, select it saved it and did a test, bam, the gauge needle and pcm read the same speed now, i tested it againg those police radars, right on the spot, so my theory is that efilive does not write to the proper tables on the pcm, i've read numerous post on another forum of people changniog a setting for the po420 and the error still popping up no mather what he disabled, or like me having the program tell you it was written but in fact something went wrong as the tune would not take, my speedo issue is fixed and i got a case relearn doe on my stocker pcm, but now i am worried about having efilive to do my tunes, could someone please tell me if what i'm experiencing is just my imagination, because my numbers don't lie, and my scangauge does not also,

is it because of my OS ? A few members here tried the g1021 setting changed to 25v for the po1481 disabling, on my end nothing, I still get the code if i unhook my magic trick, but some others report it works flawlessly, so what's up with that ?

I'm worried here