i have a autometer oil pressure guage that has never been installed. but the sender has been throw around in my toolbox for a couple months. so i decieded to hook the guage up outside the car and throw 40psi of air from a compressor into the sender to see if it would read before i installed it. well the guage didnt move at all, so i was wondering should the guage work on air pressure, or will it work only with the oil pressure?

 

Air is compressible - oil much less so. You need oil pressure for it to work.

 

I have an electrical one of these and I heard I still need a sender to get this to work but why? Can't I just hook up that one wire left to my oil sensor(also only one wire) on the back of the block?

 

your stock oil sending unit is not calibrated for the autometer guage... well atleast i think it's not.

 

why isn't it? Have anyone tried this?

 

The thing on the back of the block is just a switch not a sensor. When pressure drops below 5 psi the light goes on telling you its too late. Just removed that POS and put the gauge sender on the block in its place.

 

i put the Auto meter mechanical guage in my car and this is what i did

the problem that i have come acrross with putting the electical one in other peoples cars is that when you put the autometer sender (an you have to do this)
the vibration of the motor will snap the nozzle on the sender. if you want to use the electrical guage then do this
hope this helps