Cleaned mas. new plugs(old ones were nice colour) / distributer/ rotor / cleaned egr / pcv good / air cleaner / (new wires not installed yet) cleaned throttle body,. Starts fine. Drive around town good.Hit the gas ....it bogs......But if I feather the peda while accelerating, I can get it to move. Feels like its missing. The odd time I'll take off and its perfect....Then right back to the sluggish drive. Changed pre. cat. O2 sensor . ( fuel gauge is on way out) showing a 154 code. Really like the truck.... ( Has 150,000km) Oh I did pull the o2 sensor as a cat. Converter test. Did not seem to change performance. Thanks Forum Folks