ok. i need some ideas here. truck started running really rough, sputtering like it was a clogged fuel filter, something like that. this is what i have done.
-new fuel filter
-new cap and rotor/ plugs and wires
-new fuel pressure regulator
-messed with the timing
-air filter is fine

Anyone have some ideas on what i can check? is there anything thats a known problem that maybe i havent thought of? thanks for any input

 

you checked the fuel pressure?

 

Sputtering is usually related to poor fuel delivery, wrong timing setting, or in most cases a bad ignition coil or igniter, giving the year the ignition may have an electronic igniter. The worst case scenario is that with the new plugs delivering a more potent detonation the head gasket could have given up, check for cylinder compression and for missing coolant, I hope this helps.