Car: 2000 B5 A4 1.8t ATW quattro
Mileage: 100,620 km (~60,000 miles)
Ambient temperature during drive: -15 to -19 C (~1 F)

Last night I went on a ~400 mile round trip drive, all freeway driving at a constant 70mph, give or take. Throughout the drive the engine misfired constantly; it would stutter once or twice, then be fine for another 6-10 miles, then misfire continuously, enough to stall out the engine. I had to pull over multiple times to restart the engine, using a lot of throttle to keep it from stalling out, blipping through the 1k-3k range until it would seem to stabilize and I could continue to drive for another 10-15 miles or so. After a while as soon as I felt the first misfire I would bring the car into neutral, let it coast, blip the throttle through the rev range until the engine stabilized, then continue driving (this saved a lot of time compared to pulling over)

Codes pulled at the end of it all are as follows:
P0102 - Mass or Volume Air Flow Circuit Low Input
P0300 - Random multiple cylinder misfire
P0301 - Cylinder 1 misfire
P0302 - " " 2
P0303 - " " 3
P0304 - " " 4
P1128 - Long Term Fuel trim mult. Bank 1 System too lean

Fuel filter and spark plugs are new within 25k miles. MAF is new within 10k miles. Misfires on all four cylinders rules out a single coil pack or related problems. Here's why I think it's fuel:
At the start of the drive, I filled up at Esso for the first time in months. I usually always fill up at Shell with V-Power 91. Back when I first bought the car, I filled up at Esso before a 600 mile drive and experienced similar misfire problems. Eventually I was able to fill up at a Shell and get some gum-out fuel system cleaner in there and the misfires mostly went away, after which I replaced the fuel filter and problem was fully solved.

Has anyone else experienced problems with Esso fuel? Or is there any explanation for why Esso fuel + cold weather + highway driving = unhappy 1.8t? I filled up at Esso once in the summer and had no problems whatsoever on another 400 mile drive. I have since gotten a quarter tank of Petro Canada 94 and half tank of Shell V-Power 91 into her, short drive around town this morning and no problems. Any help is appreciated, sorry for long post.