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What affects oil pressure?

1460 Views 6 Replies 6 Participants Last post by  n0alpha
I only have this car in my possession for the past 3 months. I have observed that sometimes, during idle at a stop light after the engine has warmed up, the gauge reads at 2 and when I drive, it goes back to 3. When I start the car in the am and during idle, the gauge is at 3. Is something "stuck" causing it to be at 2 during idle at the light after the motor is warm? Or is this normal? It also sometimes "twtiches/bounces" back and forth around 2 a couple of times and then settles at 2.

The car had a valve job 18k mi ago. The rings were supposedley (sp?) checked during that time.
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Sounds perfectly normal to me.

When the engine is cold, the clearances between moving parts are at minimum and the oil is more viscous, resulting in a higher working pressure. As the engine and oil warm up, the clearances increase and the oil viscosity decreases, so at idle you would expect to see a slightly lower pressure. On these cars, they tend to be at 2.

One does not need to worry unless the pressure is high with a cold engine, but is really low (< 0.5?) with the engine at operating temperature of 80 degrees...that would indicate major engine wear.
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