My ac cools just fine, the problem I,m having is it will quit blowing out of the ac vents and start blowing out the defroster vents. this happens when I'm going up hill or in some strain.
I think its a bad vacuum check valve. only problem is I don't know where the check valve is.
does anybody know where the check valve is located or if it might be something else?
RRW (Rebnutt)

 

Reb, welcome here, and I can't help with that. But, somebody here will chime in soon. Put all information about your Dakota, year, engine, etc., just like you have to do at parts store. That will help.

 

the FAQ #1 has links to service manual for a few years. pick one close to yours and download it to your hard drive. has a good section on heat and ac. my 1995 does same thing unless I put it on recirculate. I plan on fixing but haven't done so yet. good luck