The generic OBDII DTC isn't the same for all makes and models. A generic P0048 would normally be "Turbo/Super Charger Boost Control Solenoid Circuit High", but you've found the trouble with that already

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I've got an
OBD-II reader coming in when I get relieved in the morning. I'll look it up on there if he brings it in and get back to ya. We've all be fighting trouble codes the last two months it seems and that thing is getting loaned out left and right! Comes in really handy.
But that seems very familiar. Is that not a vacuum leak(minor)? I think the P0049 is vacuum leak(gross). Could just be the gas cap if so. Anyway, I'll check in either way.