I'm begining to think that the 275 might be too much on hotter temperture days. I know of 3 different trucks in San Antonio that have the 275 that have had this happen. One has NOT had it happen with his 250 though.
The day I got V3 of the 275 was hot. I defueled on the way home from work a few times & had hoped that after loading the new tune it wouldn't happen. It did & I logged it for the first time. I then loaded my 210 & ran it hard but it didn't defuel. The next thing I had done was having my FRP sensor replaced. The weather wasn't warm again for a couple weeks here in Texas & so I had hopes that replacing the sensor had fixed it. On my way home from a buddies ranch in west Texas towing my ranger & some other stuff I went to pass a car. I had the pedal to the ground & was almost around them (only going about 75mph to pass) & the truck defueled, slowing me down instantly. Luckily, they slowed down to allow me to get over & i did my usual routine of putting it in neutral, turning it off & starting it back up while driving. Outside air temp was 91º that afternoon. After I dropped the trailer off, I defueled 2 more times on the way home & have been on every hot day we've had if I get on my truck.
I wouldn't say that there is something wrong with the tune itself, just that it throws the code & defuels the engine on the hot days.....
I'm going to ask Spartan
if they'll send me a 250 tune I can test. I love the 275, but cant run it on hot days which will only get more & more often as summer comes.