I recently bought a 1993 Camaro Z28. I drove from Michigan to California and on the trio in the last hour my oil pressure dropped and engine temp started rising at idle. I replaced oil pump the sending unit(pressure switch) pick up tube and screen but am still having the issues.

 

dropping oil pressure??

what does your gauge read at idle when it drops?

If you have a cooling system issue making the motor run hot, that will thin out the oil some and cause oil pressure to drop. "Maybe" you have a cooling system issue. If not low oil pressure is rarely due to a failing oil pump. bearing wear is the more common cause. Only real fix if that is the case is a rebuild but a band aide short term fix would be to use thicker oil like 10-40

 

Oil pressure drops to about 10-15 Rpms go low as well.

 

10-15psi of OP at idle is normal for a SBC...assuming the gauge is right

general rule is on SBC, OP increase 10 psi for every 1k increase in RPM. Bypass valve in oil pump opens up if pressure gets to high

You may have low oil pressure due to worn bearings....but if engine temps are going up when you are at idle...I would confirm the cooling system and fans are working correctly to rule engine cooling in/out as the cause.

 

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