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Discussion Starter · #1 ·
The oil pressure gauge has always marked very little pressure (almost nothing). Like a year ago I started to panic since I had replaced the sender thinking that that was the problem yet saw no positive results... I quickly checked the pressure with a mechanical gauge and the numbers checked out fine so I knew everything was normal internally. I let that be until now, because now it is really bugging me!

I want to know how to fix the problem. So far I have grounded the gauge directly to the engine and the needle did a full sweep. Does this mean the gauge works? I also changed the sender 3 times with no positive results. What else can I test to see what the problem is? I also have an aluminum extension from NPD, could this be the problem? Or is it simply that the gauge has given up the ghost? Thanks in advance.
 

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Your gauge is working properly.

Question: does your gas gauge read correctly, or does it read low?

If the latter, you can adjust the output of the constant voltage regulator on the back of the dash cluster to have the gauges read higher. I adjust mine so that the gas gauge reads correctly at 1/4 tank. How to adjust? There's a trim pot, screw, or post epoxied in on the back side. Just remove the epoxy and turn the post one full turn and then check your gas gauge. Adjust as necessary. Please disconnect and reconnect the battery between each adjustment.
 

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Discussion Starter · #3 ·
The gas gauge reads correctly (well If I were to be picky about it, it is about a millimeter or two away from the "full" mark, but I doubt that will make much difference.) Thanks anyways, I will try adjusting that to see what it will do. But I am afraid that with my luck it is a far more diffucult fix :( .
 

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I presume you do have the right sending unit? The ones for idiot lights are different than gauges.

Additional resistance in your oil sending circuit is ruled out, as that would cause the gauge to read high. There's really nothing else left...
 

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Discussion Starter · #5 ·
See, I told you I had this kind of luck. I do have the corect sending unit, and have replaced it 3 times. Although, the PO had swaped in a late model 302 and the gauge was hooked on to a non- working light sending unit when I purchased it. Could this have ruined the gauge?
 
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