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Oil pressure gauge problems

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Old 12-30-2012, 10:51 PM
  #1  
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Oil pressure gauge problems

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?
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Old 12-31-2012, 03:26 AM
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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?
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Old 12-31-2012, 03:30 AM
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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?
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Old 12-31-2012, 09:17 AM
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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?
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Old 12-31-2012, 09:34 AM
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Oil pressure reading intermittently

Originally Posted by MurphyEF
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?
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?
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Old 12-31-2012, 11:03 AM
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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.
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