astro idle and charge

thankyou for looking....ive two problems ...the ide on the van is very rough and goes from nothing to normal up and down sometimes it will do it somes times not getting worse lately...i get a code 32 and 12 ..12 means its fine and 32 does not apply to a chevy but a caddi /olds/buick...?wierd...ok as for second problem...i cannot get the alt..to charge with out touching the brown wire to a 12volt source,,everytime...started when i changed the dash to digital ...i put it all back the way it was And it still does it...help on all please thankyou..soryy its a 95 astro with a 4.3 vortec

First, the "32" does apply to a Chevrolet. What year/engine is involved? It's usually a MAP or EGR error code, but knowing the year would help.

As for the charging system, there are multiple possibilities. The brown wire for the field is usually connected to power through a slight load:

http://72.19.213.157/files/TPI-Charging.jpg