I've been fighting why my Long Term Fuel Trims have been so high - LTFT1 and LTFT2.
They are supposed to be close to zero.
I use the Torque Pro app on my Android phone.
I replaced the MAF sensor and it seemed to be the solution but a few days later they rose back up.
Finally I think the reason is the Gas Cap which I typically just tighten to the first click.
I read somewhere that the Gas Cap could be the cause of "false air" ... so now I tighten it till it clicks and then some more.
Here are my Fuel Trims while driving:
View attachment 2880877
... and at idle:
View attachment 2880878