Rock Auto is sending me a new one.

By brand new chinese sender did the same. I'll keep the OEM sender off the donor Buick motor to replace it.

Something to consider is when the senders go bad, typically the oil seal blows out. This can lead to oil in/on the connector. A clean connector is a happy connector.

Pulling on the wires can lead to future problems. as they may break over time and engine flex.

Yeah, I know, that'* why I didn't jerk on them. More of a slow stretch to get the wires to bend around some corners better. I didn't have too much of a choice short of splicing in some more wire.

The connector was clean. I had an O'reilly generic replacement in there and just figured I'd replace it before it went bad... lot of good that did...

And, now that I think about it, my oil pressure never got much below 20 with my original sender. I put in the O'Reilly unit during the last oil change on the old engine. Right before the indicated pressure dropped to 10.

Well sumbich....

Got a new one from Rock Auto this week, and I put it in earlier this evening. It made the gauge behave the same exact way.

So I got down to diagnosing. Multimeter came out. FSM came out. Original OEM and recent O'Reilly brand senders came out. FSM says which wire should be ground and power. Check... FSM says what the resistance in the sensor should be at 0 psi, 17 ohms. Freshly removed "BAD" sensor shows 4.6 ohms. Hmm. I reach in and test the new sensor, and it shows 4.7 ohms. :? Ok, recent O'Reilly unit shows 0.6 ohms. Odd, that'* even further from 17 ohms. Old *** original shows 0.8 ohms.

I put the original back in... and wouldn't you know it, it works just fine. It always did, but I just wanted a fresh one, so that'* why I got the O'Reilly unit. And just recently decided I didn't trust it too much, even though it seemed to work fine. That'* why I ordered a new AC Delco unit.

So, now my question is... does my car just need a different sensor then AC Delco thinks it does? Are they both actually bad? The only visible difference between the two that work for me and the two AC Delco units is body length. The original and O'Reilly are about 3.5" long, and the AC Delco units are 2" long.

Any one have a known good sensor they can check the resistance of?

JW, im worried about the difference in the length of the physical sender. i know when i had an issue with my 93 there was only one sender listed and it was the exact same size as the OEM

i would double check to make sure that RA sent you the correct one, and make sure that the PN is the same as the OEM

Well, RA has the same part number listed as AC Delco, and it'* the same number printed on each box.

If anyone can test theirs or a spare lying around, it'* the pins circled in red.