Rep Power: 0

Only CEL in the dashboard is p0420(bad catalytic converter) and the only thing that doesn't seem to work is the A/C.

 
Rep Power: 367

is your low oil light lit? That seem to be oil pressure sender. Is there a light in the dash? previous owner might have removed the bulb from dash. Does it lit when you turn key to position I without starting engine??

 
Rep Power: 224

At first I thought it looked more like a knock sensor, but I see two wires so that's not the case. I think that eliminates the low oil light switch as well.

Where does the harness go? It doesn't look like it ties into the main harness. Maybe this is an aftermarket sensor and the gauge inside was already removed.

 
Rep Power: 0

Yes the oil light is on when I turn the key so the bulb is there. Still possible this is oil pressure sender?

 
Rep Power: 0

Goes to the main harness it seems
Oil light is on when I turn the key so the bulb is there

 
Rep Power: 224

I found it. Power steering pressure switch. This sensor would tell the ECU when the power steering is under high load so the idle could be bumped up a little.

 
Rep Power: 367

woah, good catch

 
Rep Power: 222

I think one of the lines you can get doesn't have the sensor

 
Rep Power: 0

Thank you very much! That might explain why the car vibrates a little when I turn. I thought that was normal behavior for an old car

 
Rep Power: 224

Now to figure out why that sensor isn't in the hose. Does the hose have a plug in the port for that sensor?

 
Rep Power: 222

You can buy the line with or without provisions for the sensor, it was probably a couple dollars cheaper, and whoever did the repair didnt bother looking.