P0101 and lean condition - redux

[47_MasoN_47]

It's been nearly 2 years, but the problem I posted here briefly returned while I was about 400 miles from home last weekend - http://www.yarisworld.com/forums/showthread.php?t=48749

I suspect perhaps it's fuel related. Both times I had filled up at somewhat sketchy looking gas stations (unfortunately that's all that was available to me last weekend). Anyway, I stopped for fuel, made it about 50 miles, then stopped at another gas station to take a pee (that 50 miles took nearly 2 hours thanks to horrible traffic on I-65 below Montgomery). Start to leave the gas station and the car's coughing, barely accelerating, surging around, etc. I turned the S/C off, then turned the car off and on again and it still was doing the same thing. Made it a few feet down the road and it threw a CEL. I pulled the codes and it was P0101 and lean on bank 1. Last time this happened it took a long time for it to go away. This time I just left the boost off and drove down the shoulder of the interstate holding the brakes to keep the revs high and the engine under load. After maybe 30 or 45 seconds of doing this the revs settled out and it stopped sputtering. I cleared the codes and drove it about 20 miles with the boost off (felt like I was barely moving, lol). Codes didn't come back, so I turned the boost on and made it the remaining 300 or so miles back home without problem. Once back in town I added some proper fuel from a Shell station and put some gumout fuel injector cleaner through it. I dunno if the injector was clogged or what exactly happened. I'd love to hear thoughts on what it may be.

For those not familiar with my car, I'm running a Blitz S/C with AFE intake and injectors from a Celica. I still haven't installed that AEM F/IC I bought (I know, I know) a year or more ago, so I don't really have a good idea of what exactly was going on. Car's been fine since then, but I'd really like to know what causes this.