90 Coversion van ,,Map and Tps out of range codes??

[Jim Adams]

I have a 90 conversion Van and it has a 5.0 ,,,I was doing a self test on the ecm and the ground in the pig tail for the diagnostic link only had limited ground and wouldnt enable me to get a reading,,I was using the volt meter method of self testing,,so I added ground to it,,and I get a code 22 and 23 now prior to this it wouldnt start hardly and when it did it smelled like real bad diapers and blew black smoke ,,then when I added the ground it started and starts right up now just doesnt run just right and gives me these codes,,is my problem in the computer since that is where the ground is bad or is it the Map and the TPS.