Engine seems to be vibrating and sounds a little rough.

 

Did you do anything else when you did the timing set? Did the distributor get turned at all? Cam or Crank while chain was off?

 

The crankshaft was turned to line up the marks. And the distributor cap was off during the replacement

 

Which marks? To set fuel sync, I don't think that is set at TDC.... Have a service manual for your truck yet? If not, get one here. Setting initial fuel sync process is in there. (look in the engine section, under distributor remove and replace)

 

So other than marks lined up I need to do something to distributor?

 

Hhhhmmmm....... Thinking on this a bit more.... if you had lined the dots up wrong, the engine wouldn't even start... (180 degree out on timing) If you didn't disturb the distributor, that should all be good.

Are you just getting a bit of a miss at idle? What kind of shape are the rest of the ignition parts in? (cap, rotor, wires, plugs) Is fuel pressure good?

Given that your chain actually broke....... You may want to do a compression test. As I think pistons can actually meet valves in these motors. Not 100% sure on that though.

 

I replaced cap rotor plugs wire. And coil camshaft positioning sensor and fuel pump was replaced about 2 months ago.

 

Is it missing immediately at startup? Or does it start missing only after running for a couple minutes?

 

After a couple minutes

 

Front O2 sensor could be bad