Chevrolet Repair: 98 blazer idling and electrical, convenience center, side mirror

Question
my 4x4 LT just recently started idling rough at start up but smooths out after approx. 1k-1500rpm. i added fuel water treatment w/ no avail. Also @ 1yr ago, if my memory doesnt fail me, the rear washer stopped pumping water, the external rear glass switch stopped working, and the pwr.side mirror switch quit all at about the same time. Ive checked the fuses and they all seem to be fine.  

Answer
Hello Earl,
I would first try some injector cleaner through about half a tank of fuel.
I would like to stick a fuel pressure tester on it to see what it shows. Does that just happen on first startup of the day, or every time? Fuel filter may be a solution, but the pressure test could confirm that.
Under the hood should be a convenience center with a bunch of fuses and relays. Find one that is marked something like accessory relay. I would swap it with one of the others that has the same part number, like trailer lights,blower motor, or power seat, etc. to see if that fixes it. You can try the other system to see if that relay is good.

Van