wont run when warm

I just bought a 93 blazer with a 4.3. It has been sitting for about 3-4 months because the guy couldnt get it running. At first it would not start at all but i changed the plugs and it started right up. All the plugs were fouled out pretty bad.  Now the truck will not idle when it is warm, it just sputters and stalls.  If i hold the pedal to the floor it will start back up but never idle.
 
It also runs rich and blows black smoke when it is running.  Any ideas on where to start? I was thinking the egr first.
 
Thanks,
 
chris

Whats the fuel pressure at?? If you have a fuel pressure tester, test the fuel pressure to see what its at.

TBI or CPI?

If CPI, fuel pressure is the first thing I would check.  If the plugs were fouled, the possible reason for parking it could be a faulty fuel pressure regulator.  There is a ton of information about that on the forum.

If TBI, then it could be a leaking throttle body gasket.

For either case, the EGR could be at fault as well.

its a TBI, thanks for the info...i will check the for leaks and pull the egr and clean it up.
 

Let us know what the results are of your inspection and cleaning!!

Being TBI, with the air cleaner assembly off the motor, watch the fuel spray.  It should be a fine mist.  When the truck starts to act up, does the spray pattern change at all?

here is what i found so far, after i put brand new plugs in and all 6 plugs fouled out in about 1/2 hour to the point that it will not even start now. i pulled the plugs out and cleaned them all up and now it just sputters and pops but will never run. it is getting fuel and spark.
so what would cause it to foul out all 6 plugs that fast?
 
i did notice the oil was about 2 quarts high and the pcv valve was all full of oil. there is no water or debris in the oil it is just dirty.
any suggestions would be great.