Well, I finally got the truck fixed. I had a lot of trouble finding a time when I could actually take the thing in, so I had a lot of time when I was just unable to bring the truck in. Anyway, after about 31 hours (mostly waiting for parts), they got it fixed. It was a bad rotor and distributer. I also had them replace the spark plugs and their wires as well (since they were pretty much due anyway). All in all, it costs about $500.