I suspect my oil sending unit to be bad because the car still runs fine just reports dangerously low oil pressure, where should i hook up a mechanical one to check? Also where exactly is the oil sending unit?

 

The stock oil sending unit (mid 94 to 97) is on the top of the block, behind the drivers side corner of the intake manifold, under the cowl.

There is a plugged port right above the oil filter that can be used for an oil pressure port. It was used for the stock pressure sensor 93 to early 94.

Shoebox has photos of both these on his website:

http://shbox.com/1/4th_gen_tech1.html

 

I belive you sending unit is behind the Intake on the Drivers side behind the EGR Valve.
http://shbox.com/1/oil_pressure_sensor.jpg
It's about 3" long and should be pointing twards the Pwr Boster.
It takes a 1 1/4 socket to get it off.

 

Man you beet me

 

That's where my mechanical unit is plugged in.

The stock sender and gauge is surprisingly accurate, it doesn't respond quite as quickly as my mechanical gauge, but they're usually not far off from each other.

 

Since your question was answered, I hope you don't mind me asking an additional related one. Should any mechanical gauge screw into either one of these places?

 

The threads have to match. There are adapters available. The one on the block above the oil filter can be a problem if you have headers. I have a mechanical gauge, and there is a brass elbow screwed into the hole in the block, and a -4AN hose running from the elbow to the oil pressure gauge in the center AC vent.

Per Shoebox's photo, the threads on the port above the oil filter are 1/4" NPT:

http://shbox.com/1/aux_oil_port.jpg

 

The autometer sport comp 3421 mechanical gauge threads into the bottom port just fine with included adapters, can't tell ya on the top side.

The 3421 worked just fine with my LT headers if that helps any, the headers weren't anywhere near being in the way.

 

has anyone ever had trouble with leaking inside the car on a mechanical gauge, i am sick of dealing with electric senders...i dont' trust them

 

I used a -3AN braided S/S hose. No leaks. I would not use the plastic tubing that AutoMeter supplies.

 

i have never mounted a mechanical gauge, how does the tube or hose actually attach to the back of the gauge...what prevents it from busting off under higher pressure

 

It's called a pressure fitting.

 

I agree with what Fred said, do not use the crappy plastic tubing that autometer provides you with. There is just not a whole lot of clearance behind the gauge cluster to be using that kind of tubing. Just go get yourself some 1/8" copper tubing or a steel braided line and use one of those instead. Me personally I used the copper tubing but I would have liked to go with the braided line instead but didn't really have much luck finding any locally.

 

i should have responded to this, it went great. hooked up an old mechanical gauge at that port by the oil filter and good a good reading, so i went to autozone and got the pressure sensor and put it on. BTW they make a special oil sensor socket that makes the job a lot easier, autozone let me borrow it