'96 T&C Windshield wiper question

My windshield wipers ONLY work if 1) I press the thing in to wash the
windshield or 2) after the engine has been driven for (depending on
outside temp) an hour or so.

AND THEN it only works on the 1st click--which would be
intermittent--(none of the other clicks work) but it is the speed that is
about the 3-4 click--not fast but also not intermittent.

I have put on a different signal arm and WW motor from a wrecking yard
Dodge Caravan but that changed nothing.

I'm stumped!

John