Just recently the oil pressure warning light would come on at idle once the car was at normal running temp but would go off again if revved or driven. I had an electronic oil pressure gauge installed & once the car was warm it was reading 0psi at idle.
After a bit of research online I was pretty convinced that the least of my worries was I needed a new oil pump. But before I went any further I dropped the sump off & pulled the oil intake out, which looked to be partially blocked. So I gave it & the sump a good clean, put it all back together, filled it up with fresh Castrol Magnatec 10-40 put on a new oil filter & it seems to have solved the problem. The oil pressure gauge now reads around 10psi at idle which I hope is a crap load better.
I was wondering now if anyone out there knows what the normal oil pressure readings are, as I can't find any info about this.
The car is un-modified apart from an HKS Pod filter, BOV & a full 2.5" Ralliart Exhaust system.
Any help would be much appreciated.
EVOLVE

 

You should see about 14-28 psi at idle. Expect to see highest pressures after a cold start then it evens out (around 23-25 for me). That said my oil is a lil thicker than yours.

 

Well, for 22 year that I know of the oil switches on the 4G63 have been set to come on at 4 psi.

 

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