I degreased my engine bay today, covering the air pump filter, air filter and diagnostic connectors. After letting all the water dry I finished the cleaning process with carb cleaner, 5-10 minutes later I started the engine and the oil pressure went straight to 110psi at 1200rpm, with the AC on at 750 rpm it goes to ~55.

While trying to diagnose I noticed that my sending unit wasn't even hand tightened so I torqued it properly. After realizing that I might have gotten water in the engine through the sending unit I drained the oil and changed the filter, still no major change. At idle its at ~55, 3000rpm gets it up to ~100.

I checked the back of the cluster to check if the connector was crimped and also cleaned the sending unit. 20W50 Castrol GTX, cheapo fram filter. What could this be? Before doing the oil change it would sometimes go to 30psi with the AC on at 750rpm and then skyrocket as I applied throttle.

 

If the sending unit was loose, there would have been a major oil leak.

Sound like the sender has failed causing the gauge to read incorrectly.

 

So I switched the pressure sender to some old universal one I had laying around and that one reads ~40 at idle and goes to 70 at 4500 rpm. Thanks for your help.