Helliekat

I drive a 1998 Forester I've had it throw codes quite a few times now. First time, a month ago, there was a lot of lurching, it was repeated misfires. Got sparkplugs changed (went with NGKs) and new plug wires as well. Ran nicely after. I had it diagnosed at an autozone, so while I think it was 3 and 4 misfiring, I didn't get a look at the exact diagnosis so I'm not 100% sure. Second time, used my OBD II reader, 3 & 4 misfires. Had them pretty consistently, swapped the coil pack. They seemed to stop. The engine threw the same cylinder 3 and 4 misfire codes on the way home today. I've heard from friends that injectors seem unlikely since the misfires wouldn't be this random if that were the issue. Not all that sure where to go next. MAP sensor or vacuum leak? Possibly irrelevant facts: 1. Swapped my clockspring last night. Successful. Airbag light is off and horn and cruise work again. 2. Driving (or trying to drive) from Ogden, Utah to Oshkosh, Wisconsin in 3 days. Joy.