Yesterday morning I started up my 1988 GXL to warm it up for a few minutes before taking off to Paso Robles. I immediately noticed the oil pressure gauge was flatlined at 0 psi, so I opened the hood to check the oil level and look for huge leaks. I did find that there was a leak coming from the base of the oil pressure gauge unit at the rotor housing, but it only leaked while the engine was running. MY CAR HAS NEVER LEAKED BEFORE! I turned off the engine, and the oil leak stopped, so the pump has to be working, right?
So I start it up again, start driving it and the gauge (which was at 0 psi again uon second stat-up), jumps to normal operating reading, around 50 psi or so after about 30 seconds of driving. I drove all the way down to Paso Robles and back yesterday a distance of about 250 total miles, and the gauge was fine all day long, even though I stopped and started the engine sevral times during the course of the day.
Do I need a new oil pressure sensor that goes to the gauge in the cluster, or is there some sort of electrical problem that I should track down?
And if that's the case, why did it leak and then all of a sudden stop? Your advice and information is greatly appreciated. Thanks

 

Hmm - the sensor is leaking, and the gauge signal is intemittant.

Best bet - the sensor is failing. (but you already knew that)

 

I figured the sensor was bad, but I just couldn't figure out why it would work and stop leaking. Theoretically, once it went bad, shouldn't it stay bad?

 

Depends on whats wrong with it Dude....lots of failures can be intermittent....I got my new sensor unit from Pep Boys when mine failed....$39 and its good as new....yours may need screwing in just a little since it is leaking...its either that or most likely the diaphragm is failing....get a new one...be careful...the temperature sending unit just below the sensor is easy to damage during replacement...

 

Thanks for the information guys

 

You need to drain your oil (some of it, at least), remove the sensor from the housing, and clean up the threads on the sensor and in the housing. The threads are the electrical ground for the sensor circuit, and we all know what dirty grounds do for our cars. Reinstall after cleaning, and see how she does...