I'm new to tuning and just wanted some input on my logs.
Vehicle: 2016 BRZ Manual (US)
I've had an OFT and the stage 1 tune for about 4 months. No logs from that time.
In early January, I installed an FT86SpeedFactory catted UEL header and flashed the Stage 2 tune. It ran a bit rich at first but seemed to adjust nicely with pretty low or non-existent fuel trims and the kind of knock adjustment you'd expect with 91 gas (IAM was sitting around 0.65-0.75).
Then a week later I installed the OFT Flex Fuel kit (EVAP sensor), still running 91 gas (although from a different station that normal - maybe this is also a factor). It did not seem to do well on this tune, or maybe with this gas, I'm not sure which. IAM ended up going all the way down to 0.0 eventually.
The IAM then shot back up to 1.0 after about 20 miles on E85. The engine seems much happier on E85.
I have included logs for:
-Stage 2 tune just with the header installed, but no Flex Fuel sensor installed yet after a week.
-Stage 2 Flex Fuel tune with the flex fuel sensor installed, but running 91 gas after about a week.
-Stage 2 Flex Fuel tune with E85 after about a week.
The flex fuel tune seems to have around 7-10% total fuel trim (LTFT sits around 8%) when there is no engine load or at idle regardless of whether it's on 91 gas or E85. The higher fuel trim numbers at low load only started with the flex fuel tune (and sensor). I did not install any other hardware.
I'm not sure how much of a problem this is, or if it indicates a vacuum/exhaust leak. The only source of a vacuum leak I can think of is if I bumped the brake booster hose when wiring the ECA sensor, but it seems firmly attached to me. I've already re-torqued the bolts on the header twice (22ft/lbs) and saw no indication of an exhaust leak.
The only other thing I can think of is the Flex Fuel tune is based on a catless header and maybe that is messing with the fuel trims.
Any suggestions? Is there even anything wrong here?
Thanks
https://datazap.me/u/98gsrsn/1-oft-stage-2-no-flex-fuel-kit-installed-yet-91-gas?log=0&data=1
https://datazap.me/u/98gsrsn/2-oft-stage-2-ff-tune-flex-fuel-kit-installed-91-gas?log=0&data=1
https://datazap.me/u/98gsrsn/3-oft-stage-2-ff-tunes-flex-fuel-kit-installed-e85?log=0&data=1