I'm on the second month with my 97SSEi now at 52,000 miles and the oil pressure guage is acting funny. It used to be that with each acceleration and deceleration the needle would smoothly go past the 40 psi mark when accelerating to highway speeds and then smoothly go back down below the 40 mark when slowing down. Now all the sudden the needle almost alway stays a needle-thickness below the 40 psi mark no matter how fast or slow. every now and then when at idle in traffic it'll move erratically past the middle again then suddenly settle to the normal under 40 spot. Come to think of it now that I write this, before the above problem was happening the guage would move well past the 40 psi mark at highway speeds near the 60 and the pressure would have a hard time coming back down when at a stand still though it did so very smoothly.

What could this be...a sending unit, oil pump or something else? If the oil pressure is actually much lower than previously, would I hear knocking/pinging or otherwise wear the engine down?

Thanks,
-Jason

You're in no danger whatsoever until you start falling below the 20 mark. Keep driving the car as the problem is diagnosed.

My first suggestion would be to put a mechanical gauge on the car, and compare readings. If it'* off significantly, replace the sending unit.

ya, do what will said, we did that on the 94 and it sure enough was the sending unit, after that, it stays where it is supposed to, for the most part, it stays from 40 to 80 psi depending on engine temp and driving situation, on hightway it stays around 70 psi and in city it is at like 50 or so, but all is better since testing with mech. gauge and finding it was the sending unit

Im having a similer problem with mine except that mine every now and then it goes all the way to the end and starts to bounce there...i have a mecanical gauge in my piller pod and it reads that the oil pressure is fine, is it just the sending unit like willwren said or was that just the first place to look into with other thing that might also cause this problem??

I am betting it is your sending unit

We've seen many members with crazy gauge problems on 92-95'* and typically it seems to be cluster related. On the 96+ if there is an odd reading the solution is typically the sending unit for that gauge.

I had a similar problem with my 93. Turned out to be a broken wire leading to the sending unit. Would work, then not, then drove me nuts. When it didn;t, it pegged the gauge. It does sound like yours may be the sending unit. Take Bill'* advice and get that mechanical guage on it first to be safe.

Thanks for the feedback. Does anybody have a picture and description of where the sending unit is located. I was happy to find out it is only $30.00 for the part.

Thanks,
-Jason

It is shown here as #6, down by the oil filter.

Could be the gauge cluster too, it'* a common problem on these cars.