Chevrolet Repair: 1993 Safari Vortec engine, coolant temp, deisel

Question
My buddy had this van with a Vortec in it. It starts ok when cold but runs like a deisel, when i say that i mean it blows black like carbon and does not run very strong, it wont start right away, when warm if at all after  a few tries. We have replaced IAC, which the dash code was flashing no luck. He replaced the fuel pump,the ufo (round forgot the name thing..lol, usually vaccuum this one electrical), still runs black out the tailpipe.  Any insight would be great,..Thx very much.....Tim

Answer
Hello Tim, I would look at the coolant temp sensor for this problem. If the sensor is telling the computer that the engine is very cold (-30 deg) it will run very rich. This part is located in the intake manifold next to the thermostat.


Let me know how you make out

Have a Nice Day    Mark