My oil pressure guage doesnt work. Any ideas why or how to fix this?

 

make sure the sending unit is working and check the wires go to the unit

 

When the car is running, what does the oil pressure read? Is it flat a zero or is it pegged all the way over?

 

Its pegged all the way over and then some so it seems.

 

Well, it can be one of 3 things, Bad Gauge (not likely), Faulty Sensor (possilby) or just a bad ground (very likely). I would work in those directions.

The most likely is a bad ground. If you connect a test light to the plug that connects onto the oil pressure sensor, should be a single wire plug and ground the connection to a good solid ground, the light should come on with the key in the on position (not run). The next thing I would do is to remove the sensor itself, most of these are about the half size of a 12 oz soda can and can be a pain to get to depending on how it's mounted. Connect an wire to one end and ground the wire. Then run a wire from the plug connector over to where it would plug in on the sensor. If the wire now has a good ground and the sensor is good, the gauge should read at zero. If not, then you may want to try a replacement sensor, which you can test the same way before installing it. If your old sensor is good, then your problem is simply a bad ground. I would start by cleaning the connections at both ends of the relay. Some people make the mistake of using teflon tape on these, which is not necessary and can prevent the sensor from achieving a good ground.

These are the steps I took 2 days ago after having the exact same problem. It turned out to be a bad ground...

Good luck,

 

Thank you for your info. Sounds a little complicated for me. Any pics or diagrams for this. Thats usually a little easier for me especially being a female.

 

It only sounds more complicated than it is... I will see what I can do.... If you don't have it figured out by tomorrow, I'll have some pics for you.

 

I wont have time to look at it until later in the week so pics or whatever would be greatly appreciated. Thanks.

 

My Gauge doesnt work either, as its pegged past 70psi. There is a connector just chillin there by the oil filter, and when i had it up on my friends lift i checked that area and theres 2 places it COULD be plugged into, but they have metal plugs in them right now, and there is no provision up by my distributor, just another plug.

 

what kind of engine setup are you running?

 

Its the factory v-8 305 tbi.

 

I had the same problem with my 86 305, no oil pressure. I took the sensor out and hooked up a mechanical gauge just to sure I did have pressure, pressure was fine. I took a sensor out of another engine and tried it it work somewhat but then quit, so I put a mechanical gauge back in it and just mounted it under the dash till I get a new sensor. At least I can see my correct oil pressure.