Pulled 5 different OBD codes on 2001 Pathfinder! Please help.

[maus]

01 Pathfinder, 80k miles. Pulled P0300, P0420, P0430, P1145, P1320!

I know the 300 is multiple misfires, 420/430 are Bank 1&2 catalyst efficiency, 1145 and 1320 I looked up on this site as Intake valve position sensor Bank one (pass side) and Ignition Signal Primary.

I pulled #4 (I think) plug and it is NASTY. This thing is running RICH. Sooty deposits, discoloration, the works.

Am I right in assuming that it is the Intake Valve Control Soleniod causing all of these problems? It happened all at once. I figure I'd replace the soleniod and drive it awhile to see what happened. It looks like the plugs need replaced, but if its running poorly I don't want to ruin new plugs.

Am I on the right track? I have some diagnostic and mechanical ability, but no experience working on this vehicle...

Thanks.

[NISTECH]

your vehicle is or was running very poorly none of the codes are really related to each other except 1320 and 300. this indicates one or more bad coils. when a coil doesn't fire the raw fuel is not detected by the O2 sensor instead the oxygen that did not get used in combustion is seen by the O2 and the ecm thinks the car is running lean. It then adds even more fuel. This in turn sends raw fuel into the cat in large quanities[not good] I suspct both cats are done. The 1145 could be either the sensor or the solonoid hard to tell with out monitering the solonoids and valve timing sensors.