Zage Turbo Kit Install - Toyota Yaris

[Focus_Sh1ft]

Originally Posted by cdydjded

Yes, oil pressure with cold oil will always be higher than with hot oil. Oil thins out as its temperature rises. Thats where the for example 5W30 # come from. Multi viscosity oils work like this: Polymers are added to a light base (5W, 10W, 20W), which prevent the oil from thinning as much as it warms up. At cold temperatures the polymers are coiled up and allow the oil to flow as their low numbers indicate. As the oil warms up the polymers begin to unwind into long chains that prevent the oil from thinning as much as it normally would. The result is that at 100 degrees C the oil has thinned only as much as the higher viscosity number indicates.

And depending on the quality/brand of the oil you will have +/- oil pressure.

Great info, thanks. Agreed on the RPM and oil pressure correlation as well. That makes a bit more sense and would still explain the excessive pressure. The pressure was actually so great that oil was leaking out of the filter.

I think you mean build more slowly, not fall off, right?

Yeah sorry. It pretty much plateaus at 6 psi. I was thinking it may have been because of a vacuum leak from a broken bolt on the TB, but after replacing the bolt and TB nothing has changed.