In researching whether to use the factory sender or the LS sender in the LS swap I'm doing, I tested the factory LS oil pressure sensor and got a resistance vs pressure chart. I then tested the 3FE sensor, and it acts as a switch. No pressure, open circuit. Anything about 5psi, it has 43 ohms. Doesn't matter how much pressure I throw at it, it's either open, or 43 ohms anything above 5psi.
I thought maybe it was bad, so I ordered a new OEM one to test. Same exact operation, except 63 ohms instead of 43 ohms. The pressure "sender" is acting like a dummy light switch, yet it's connected to the pressure gauge. As this is not my LC, I have no idea what the pressure gauge does during engine operation. Based on the testing, the gauge should read low when engine is off, and something when engine is running, and pretty much stay at the same spot regardless of temp/rpm (it may raise a little with RPM due to higher voltage output from the alternator. I don't know if the gauge has voltage regulation)
Is this what you guys are seeing? This oil pressure switch is the same from 1985 to 1996.
I thought maybe it was bad, so I ordered a new OEM one to test. Same exact operation, except 63 ohms instead of 43 ohms. The pressure "sender" is acting like a dummy light switch, yet it's connected to the pressure gauge. As this is not my LC, I have no idea what the pressure gauge does during engine operation. Based on the testing, the gauge should read low when engine is off, and something when engine is running, and pretty much stay at the same spot regardless of temp/rpm (it may raise a little with RPM due to higher voltage output from the alternator. I don't know if the gauge has voltage regulation)
Is this what you guys are seeing? This oil pressure switch is the same from 1985 to 1996.
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