Well, I reset the ECU and it went away. I plan on cutting and soldering all my injector connections this weekend, since I just used crimp connectors when I did the mpfi wiring. It was so intermittent that I think it has to be a bad connection. The code hasn't reappeared for a day now, so I guess it's better for the meantime. I am just paranoid about running my motor too lean... that would really suck cuz then I'd have to build my bottom end, lighten my crank and flywheel, maybe get a new cam too!!