Oil pressure gauge malfunction or oil pressure spike?

[Daedalus454]

My oil pressure gauge has been acting up recently, it normally runs about 45 psi or so. Sometimes while I am accelerating it will peg out at max pressure, when I lift my foot off the gas it drops down to 60psi or so. At first I thought there was a problem with my sending unit, but wouldn't that just drop it to zero rather than max? Perhaps the problem is with my oil pressure relief valve?

I'm running a 100% stock motor with ~176,000 miles on it. I'm running the new "Triple Protect" Shell Rotella T 15W40 with a Wix filter. I have a leaky rear main seal and some valve clatter when it's hot.

 

[smcdonaldaz]

Change the sender, that's exactly what mine did. Plus it's one of the cheapest things to try.

 

[89CherokeePioneer]

Pressure drops with lower engine RPM, not the other way around. Exactly what my sender did is what yours is doing. Eventually it just pegged out constantly-though occasionally if I hit the sender with a hammer, it would read okay for a few minutes.

 

[k.smith904]

Change the sender, that's exactly what mine did. Plus it's one of the cheapest things to try.

ditto on changing the sender. My oil pressure was sitting at 60 PSI at idle, so I asked the good folks at :: and this is apparently a common problem. Picked up a new unit at Autozone for $25, took 10 min to install. Very easy fix, and if not, its a cheap place to start.

Also, check your cat converter, might be clogged.

 

[Matthew Currie]

Post -91 senders peg up when they are disconnected or open, rather than dropping to zero. If the problem is intermittent, you might try just cleaning the contacts first. If no help, then replace the sender.

 

[lawsoncl]

Also, check your cat converter, might be clogged.

Huh?