Hi. I had my tranny fluid changed today, and the guy lifted the car, and he said the "oil pressure switch". was leaking, and showed me. Looked like there was some oil on and around that part. He charged me 60 bucks to replace it. Is that a common problem, and was I overcharged?
I don't mean was it more expensive then doing it at home, but was it reasonable for this problem being fixed by mechanic? It didn't look like such a complex part, and I don't think it took him much time to change it.

 

That's the oil sending unit, right? Mine started to leak about a month ago, and I had my mechanic replace it. I don't remember the price; I'd have to look it up.

 

Also, I had them do fuel injection, Throttle body and manifold cleaning. (extra 50)
Apparently that stinky fluid injection chemical set off the check engine light. Then these guys tried hooking up one of these diagnostic tools to the ECU. He said the ECU didn't want to communicate with it. What kinda crap is that. Anyways, I manually reset the ECU myself. The guy was impressed I knew how to do that. I wasn't impressed that he couldn't get his expensive diagnostics thing to work.
I also asked the guy if I needed to change my struts. He pressed on the hood and said no. But I think I do. It's extremely rough for 15" wheels unlowered SE.

 

Sounds like you need a better mechanic. Was he using a Nissan Consult to diagnose the ECU? The oil sending unit cost me $43 (part, labor, tax).

 

PartsAmerica.Com lists a replacement Oil Pressure Switch, AC Delco #E1818 for $8 + shipping. You can probably buy this item at any auto parts chain store for about $12.

Replacing the OPS is a job which can be done by the home mechanic. Raise the front of the vehicle and support it on sturdy jackstands. Slide under. The OPS is easy to see and reach. It is "just around the corner" from the oil filter, in the rear face of the block. Peel back the protective rubber boot. Press and wiggle to disconnect the electrical connector from the OPS. You may use a special sending unit socket such as Blackhawk #30634S or ordinary 12-point 1-inch deep socket such as craftsman #47531 to unscrew the OPS. A few ounces of engine oil will dribble out, not much of a problem. You can do the whole job in half an hour, including cleanup time.

 

It didn't seem like such a hard job to me either.
The part is around 8 bucks in autozone.
I am a bit disappointed in the mechanic. I am now visiting in LA, so I really didn't want to let this wait until I got home to San Jose area. (350 miles)
This guy has been exclusively servicing my friend's cars for 10 years now, and my friend had nothing but praise. He
stuck with this guy when he just opened a shop, and when he
grew it and moved to a bigger place.
So I said what the heck, it's just a ATF change.
I guess a lot of mechanics are like that. They draw you in
with a $20 lube job, and then suck you dry on something else they find.
The only explanation I can think of was that the guy was ****ed off that he had to stay open 30 min past the closing time waiting for that part to arrive from parts store.
We got there right 20 min before closing thinking it would just be a quick ATF change.
Oh well, I really envy those of you who have garages to work on your car.

 

I am just going to start printing off these gems you give us and make a repair manual out of it. I will call it the Daniel B Martin Maxima service manual. You start taking pictures with this and we probably can publish it!