Ok, so I am new to the forums and will give a quick run down.

I bought a 96 1500 SLT Laramie with a 5.2L 318, auto trans, reg cab, 2WD from a guy who was less than competent with mechanic work. He blew the old motor and had it swapped. Can't find a date stamp on the block but the block stamp shows it is a 92-98 5.2L 318.

I am not incredibly mechanically inclined but I did buy the Haynes manual and have a grease monkey buddy of mine helping me fix her up.

So far this is what we have done:

New distributor (old one was in real bad shape)
New dist cap/rotor/plugs/wires
new IAC, TPS, MAP and ECT

She will start up and idle anywhere between 800-1200 RPM but is running very rich (fuel smell in the exhaust and a little fuel sputter out the tail pipe)
not handling load very well, having to drive an auto like a 3 on the tree to keep her from falling on her face. Yesterday when I drove home she stalled out on me and the CEL came on with P0300, P0301, P0305 and I pulled the plugs this morning and checked them, 1 and 5 were pitch black and the rest looked normal. I replaced the plugs, bosch is not as good as they told me.
when she dies she floods out and I usually have to give her 30-45 mins before i can get her to start up again.

any suggestions on why she is running so rich? I know the PCM has to relearn everything and it will take some time, but I'm thinking that there is enough crud in the engine it needs to just burn out.

I checked the cat and it not plugged

 

Multiple cylinder misfires are usually due to a blown plenum.

Replacing the distributor is going to require having fuel sync reset. Any competent shop should be able to do so. Or, if you have a scanner that can read fuel sync, you can set it yourself.

Running rich could be a failing temp sensor, (the 96 has two, a one wire sensor for the gauge, and a two wire sensor for the PCM), leaking injectors, or, a bad O2 sensor. (likely, with a blown plenum.)

Plenum can also cause rough running, lack of power, and clogged cat...... Check the stickied thread at the top of this forum for a LOT more information on that.

Welcome to DF.

 

How exactly did you check the cat? And like HeyYou stated, the fuel sync needs to be reset if the dizzy was replaced. But thats not the whole problem if it does run at least. Did you replace the pick up coil in the dizzy when it was replaced? And also check/replace the crank sensor since the motor was replaced and probably not removed before doing so.

 

I'll check the plenum, and get the fuel synch checked/reset. The O2 sensors are both brand new.

 

What brand?

If the plenum is blown, it'll eat those sensors....

 

And what about the cat?

 

Bosch O2 sensors, was all the parts store had.

 

Our trucks don't really care for the bosch sensors...... Eliminate other possible causes first, before you go ordering new ones though. (NTK, or Denso brand please.)

 

And what about the cat? lol

 

+1 more on the cat......, the crank sensor, and fuel sync....

One thing that can cause to run righ, in addition to O2 sensors and other items mentioned, is not getting enough air for proper combustion....and this can be caused by inadequate flow due to cat issue.