Sounds like you may be past this stage but future readers may be able to use this?
I did a total fluid "change", (in lieu of a flush) on my 2011 about 10 years ago, and for some reason thought it was a good idea to fashion a reservoir cap with a small hole in it that I could press the rubber tip of an air blow gun against and clear out the lines with 90-100psi blasts of air. This was before I learned that brake bleeding required bi-directional scan tool, and before they were available at reasonable prices. Well....it worked to clear the lines out, worked great actually. But when it came time to bleed, w/no scan tool, I pumped the pedal for 2 days and got nothing. No fluid no air just nothing. Eventually hooked a shop-vac up to the banjo bolt with series of decreasing diameter hoses taped together. 4hrs later, I got fluid. Took 2 more hours for the other side.
The fronts, not so much: 2 more days of pumping and shop-vac suction, and nothing. I thought I was going to burn up my shop-vac. So I sent out a Bat signal to my older wiser buddy for the second time that week. Dwayne didn't talk much, he just fixed things, every and any things lol. He came over and methodically (quietly) made an air lift out of a Country Time Lemonade bottle: Drilled two holes in the cap, put a piece of brake line in one that went from the bottom to a couple inches outside the cap, then used a hot glue gun to seal any gaps between the brake line & cap. He filled the bottle w/fluid, connected a hose from the brake line sticking out of the bottle to the banjo bolt, had me take the line loose from the master on the top end, and used the same air blow gun w/rubber tip I had used to screw it all up, to fix it. He blew air into the open hole in the cap which forced the fluid up and out of the brake line sticking through the lid, through the attached hose, and into the caliper; filling the two front lines from the bottom up, from the caliper back up to the master.....and it worked perfectly
My first Bat signal was because my piston would not seal and I could not afford a new one at the time,. The rubber looked rough! Discolored in spots and felt hardened in others. He took one look at it, didn't say a word, casually walked to my back door, knocked, and asked my wife to boil a pot of water and drop it into the boiling water for 15min (I think it was 15?)....and she came back out smiling from ear to ear....carrying what looked like a brand new piston. I reinstalled, and it's been there ever since w/no issues
Just thought I'd share for those on a budget like I was at that stage of life
