The windshield washer is not working on a 1988 honda accord and I need to know the location and the fuse is good!

I have been trying to get a sticher for the last 6mths and no one can tell me why my light is on.

2 days ago, my "check gauges" light has been coming on...noticed that oil pressure gage is dropping from normal area to nearly 0, then back up again. Seems to drop as I'm stopping or slowing to make a turn but I'd have to check that again. This morning, I went out to check the oil & nothing is registering on the dip stick at all (when cold). No knocking sound and didn't notice any problems with driving when I came home from work last night. I'm just barely over due for oil change which is what I planned to do today but now I'm not so sure that is the best way to address the problem. Called the dealership to ask price to run diagnostic but was told $100 minimum to check (which I just can't afford right now)...especially if that price won't even repair any problems.
I just had oil cooler lines changed less than 6 months ago at "The Brake Shop" and know they used "after market" parts so wonder if this problem could be related & if I should take it back there. No noticeable leaking oil this time but it had to go somewhere. Thinking maybe the seals aren't working properly?? That was an expensive repair to be having problems so soon again but I doubt they will admit it's the problem if I take it back there to be looked at again so need some advice??? What should I do? Can AutoZone check the "check Gauges" problem even though they said can't check the "service 4 wheel drive"? (another problem I've been having)
Or...Should I just go ahead with getting an oil change to see if the problem goes away first and would they be able to run codes on "check gauges" light coming on?

what do i need to do

My 2005 yukon rear window wiper will sometime go up about a foot and other times it dosent work at all. It will always go down once it comes up.

did i blow a fuse or something

My side mirror is loose and the mirror itself got scratched up in a car wash. Cost to replace or repair it? Also, there's a rattling/clanging noise under the car when I start it up, but it goes away after I start driving for a few seconds. Could it be a loose heat shield? If so, what's it cost to repair?

Back up lights do not come on when transmission put into reverse.

Replaced by Cadillac with an AC Delco 6 year battery in jun of 2009.

check engine light on plug wires are new and gap on plugs is correct

not sure when or if this has been performed.

Car has been sitting for 2 years and this was the first test drive after a tune-up.

Had it for less than a year, has 107,00 miles on it. Mechanic says he thinks the code means thermostat/cooling system problem? The first mechanic had no idea. Does not overheat, heater works ok. Very frustrating and costly

what could be the problem and how to fix it

The selector switch for my 4WD is now stuck in 4WD Low . I have tried moving it to no avail . The Chiltons manual does not cover this . I have had this truck for 3 years and not had a problem with it until today when I switched from 2WD to 4WD low , now it will not move out of 4WD low .