So, I installed a new oil pressure sender (which fixed my oil leak at the same time) and took her for a drive.......the oil pressure gauge starts off just fine, then will drop to 0 about the time it reaches halfway up the gauge.

I sprayed down the connector with electrical connector cleaner (was caked with oil) and even sprayed down the hole it screws into. screwed in the sender untill I was afraid that it might be over tight (but not like straining tight, about the same force it took to unscrew the old one) and gave her an oil change.


I feel like I screwed something up. Wires look fine. I even cleaned up a ground that was mounted to the block just up and to the right of the sender with a holder for the water hose. Anyone happen to know what this goes to off the top of their head?

 

Does it do this everytime you drive it? Guessing you are using a stock oil pressure sending unit. Sure the sending unit will work with your gauge? What about your wires to the gauge have you checked them?

 

Also make sure you are getting good contact with the connectors on the sending unit. I occasionally have my gauge read close to zero, when my oil pressure is fine. Then after a bit it will jump to past half, which is pretty much normal. I am going to investigate that here soon, and see if I can pinpoint the problem. All aside, my oil is really clean.

Also could you explain more, or show pics of what ground you are inquiring about?

 

The ground is part of the body harness IIRC and it just adds a ground to the block (which should already have a big ground from the battery->body->tranny/block). Probably doesn't have much to do with your oil pressure sender issue.

I had a leaky oil presure sender that would fill the connector up with oil then give funny readings. Cleaned it out with a degreaser and it would work fine until it filled up again from the leak. Replaced the sender and it was fine. Do you have corrosion on the connector?

 

I trust you're getting oil up to the camshaft when car is running, but have you checked the dash guage itself for continuity or corrosion at it's connector?

 

So, I did replace it with a stock style unit from o'reilies auto. It does do it every time I drive it at pretty much every rpm range. The connectors to the sender are clean and shiny, though I haven't checked how strongly they might grip the spades on the sender. Good to know about the ground. Yes, the engine and tranny are well grounded, but I dislike ungrounding wires, tbh. I have not checked the dash gauge for continuity, but I recently did replace it with the one from my parts car (the whole dash, pretty much) and cleaned everything up as I went. Also, the gauge worked fine with the old sender, it would read mid gauge when under load and around 20 or 30 at idle.