In 1988 944 out of the blue if I put wipers stock in position 1DOWN wipers don't work, also if I put in any of UP positions wipers move normally but when I switch back to OFF position wipers never come back to the bottom of the windshield. Is there any troubleshooting that I could follow to fix the problem?

 

Either bad wiper motor or bad wiper relay. Try the relay first, it's a lot cheaper.

 

My 87 did this last fall and it was the column switch.

 

I just checked that when i put the stalk in intermittent position the G9 transmitter goes TICK and switch it back off it also ticks, so i think stock is fine.

 

Same here - if I push down on the stalk I can usually get it to go. Feels like one of those problems where taking it apart and cleaning it up would take care of it, but for me it's not quite annoying enough to fix just yet.

 

This was my clue it was my switch. If I put it down, nothing. Unless I pressed it down and then the contacts would make contact and it'd work. As well, when the wipers wouldn't go back to the down position, I'd barely press the stalk up and it'd reset them to the parked position.

Unfortunately the late switches are riveted together so cleaning the contacts isn't something you can easily do. But if you do decide to tackle this, be forewarned there are springs and plates that will fly all over the garage when you drill the rivets out.

 

My early car did something similar so I did what any normal, rational owner would do... I got violent with the stalk (rapid up and down motion) and it started to work. As the others have stated, it ended up being dirty switch contacts.

 

So did I and they started working for few minutes, then I got violent again and they started working again. Do you have the number of the part I should buy? Is it whole stock or just a switch inside the column?

 

You can spray contact cleaner into the multi-switch. It has enough openings that the stuff will get inside. Move all of the stalks to 'scrub' the contacts.

You can also drill or dremel out the rivets and open it up. I used small machine screws and nuts to replace the rivets.
As noted, there are 'springy' things inside that will launch themselves up, out, across the room and end up under the biggest and least movable piece of furniture in the room. Actually opening the case inside a clear plastic bag (gallon sized ziplocks work fairly well) is a good idea.
Getting it back together is a bit 'fiddly'. You need about 5 hands to hold everything in place and then put the cover back on before they all spring back out. Patience, persistence and a bit of ingenuity help. Picks and probes (to hold stuff in place and still be able to get the cover most of the way on) also are good.

The mulit switch (with all of the stalks & levers) is considered one piece. I don't know of any individual pieces/parts available separately. I got a used one from a junkyard that didn't work quite right, and ended up taking them both apart and mixing/matching parts to get one that worked well.