Random Misfire + Cylinder 4 misfire.
Retired Moderator - RIP
Joined: May 2008
Posts: 18,729
Likes: 17
From: NH
Have you fixed the plenum yet? What about cap and rotor? Pick up coil in the distributor has nothing to do with ignition. (neat huh?) That's the cam position sensor, used for fuel sync only. (injector timing)
Pull the front O2 sensor, and take the truck for a ride, see if it drives any better.
Pull the front O2 sensor, and take the truck for a ride, see if it drives any better.