[tlorber]

I've been out of town for a while so I just got back to working on the truck. I had a blown fuse on the circuit that feeds the MAF sensor, tranny and O2 sensors. After replacing this the error code appears to be gone. Not only that, but with a "pull up circuit" (as described here and on the LSTech sites) I now have a tach signal. When I had my PCM flashed he must have changed the output signal because the tach appears to be accurate when set to the 8 cylinder setting as opposed to the 4 cyl.