gomeybear

Hello all I have a 2001 lexus rx 300 that I am trying to identify why its consuming oil and I know this has been discussed here many times. I am posting to get some clarity on the PCV valve itself. So apparently the OEM PCV valve was plastic in the 2001 RX models and was later updated to a metal screw in valve. Am I correct? If so I believe mine is metal screw in type. Can I conclude I may be free of sludge issues from this?

carguy07

My 2001 has the metal screw in type. The updated PCV valve does not eliminate the chance of sludge. In fact the settlement covered up to 2002. Might want to get a peek under the valve covers and see what's going on. Do you have any oil change history? Dino or synthetic?

Boypony

The Gen 2 valve cover (with screw in PCV) can also suck oil. See this thread to ID Gen 2 or 3 w/o removing cover.

https://www.clublexus.com/forums/rx-...-cover-id.html

salimshah

There are different discussions which overlap and readers may conclude different things. Here I will restrict the discussion to oil up the PCV

PCV: Normally a path to redirect unburnet fuel vapors (which end up in the engine oil-air space) .. these are then directed back into the air-intake.
Valve cover: This like the hat where oil is pumped up and drains down by the oil channels. Unburnt fuel ends up. At the high point the pcv vents it to the intake. There is pressure differential that helps this action.

Oil gelling: Clumping of oil which prevents normal drain down of oil

Theories that abound in RX engine (keep in mind RX engine has been changed over time ,,,, larger drain tube, larger displacement)
The oil in the valve cover foams up and rises all the way up the PCV. Why it does that? Too much pumped volume, think drain tubes, oil gelling, blocked tubes etc. The tilt of the bank 1 vs bank2 etc etc

Salim