wipers, no start sometimes, volts
 

I have a 1998 STS withh 130k miles. Great car but getting old and having a few issues with one in particular that the dealership can't seem to recreate and solve. Here's my trouble list:

The car wouldn't start. Had power and replaced battery but the ignition still went click. After the dealer tightened a cable, same problem but only now and then. I found some corrosion on the battery cable and ground and scoured them and now the car starts pretty regularly but occassionaly clicks, then I let the key return to the accessorry setting and it seems like things power up and the steering wheel tilts down to the preset location and on the next key turn the car starts up. I'm thinking it's a bad ignition switch. Another thing it does is that the voltage goes up and down a lot. 14.1 then drops to 13.2 then back up to 13.8. Usually when sitting at a light with the AC on. Ignition switch or something else or some combination?

Second problem is my wipers only work on high when it rains. The other positions don't even operate sometimes including the wiper fluid spray.

Third, anyone know how to remove and replace the cupholder in the center console? Mine is jammed in and won't release. No biggie but if it's a cheap fix I'd like to get it taken care of.

Fourth, the Service Stability System goes on now and then. Latelythe system hasbeen engaging very strongly when I make a somewhat fast gradual turn into my office parking lot in the morning. Seems the car doesn't like a turn with the bump of entering the parking lot and grrrrrrrrrrrr it engages and takes control of my steering. Then when I park it says "Service Stability System". The front struts seem pretty bouncy and may be the cause. Suggestions?

RE: wipers, no start sometimes, volts
 

Stability system should have code stored if light came on.Bad p/steering pump,debris in fluid,slipping belt can cause GRRRR. Slipping belt also can cause voltmeter to bounce - need to check belt and tensioner.Batteries have had a bad habit of leaking at the postive post for a while,GM's sealed cable design allows acid to travel into cable wire core within casing and it to corrode - check over a condition of positive cable, voltage at underhood relay center.Wipers likely cause is wiper motor module / cover.Hope it helps