Yeah Mick,LOL.
Most of the pontiacs I've been around would be happy as a clam to have 40 psi @ idle.
But yeah,the OP said that was cold so that really does'nt mean all that much to me.
Seen plenty of perfectly healthy pontiacs with like 10-15 psi @ idle hot.
And also seen a few with less than that @ idle too.
I really dont sweat the oil PSI @ idle like some guys do.
Main thing to me is what the pressure is @ say 2500 to 3500 RPM or so,as that's when the engine is going to be seeing heavier loads,and that's where oil pumps are typically rated at for testing/diagnostic purposes.
Anyhow,the Lucas oil stabilizer product,if you look around out there you can find lots of pro/con debate about that product,myself I prefer to stay away from that additive.
Actually I try to stay away from most oil additives in general,but these days I'll concede that some of the various zinc/moly/phos additives may be needed in certain oils to account for the lack of those in the actual oil itself.
So I'm not sure how I feel about this deal right now,,,especially with the seafoam/atf mix run thru it apparently "fixing" the problem temporarily and all???
So lets clear up a few details,what brand of oil is the 15w40?
Typically that specific viscosity of oil is inteded for HD/diesel use,mostly fine for these cars no doubt,but I'm just curious what brand ya'll are using for this?
And I did'nt see it stated,,,but what were the "pre problem" hot oil pressures at idle & cruise???
I only could see the stated "pre-problem" cold pressures,and those really mean nothing to me,and then I could see that the stated "post problem" pressure @ idle is down to like 7 psi,and under 30 psi @ cruise.
Where are the oil pressure readings being taken on this engine,down at the filter adapter,or up by the distributor?
Has the oil filter been replaced during all this?
What brand of oil filter are you using on this???
(hopefully not a FRAM filter...

)
What sorta op guage are these readings coming from,mechanical or electrical?
Has the gauge itself (and/or sender if op gauge is electric) been checked or not?
And just what RPM are we using for the "cruise" RPM?
Bret P.
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