The Sienna picture above is a good one - use it to find. The valve is to the rear of the engine on the passenger side almost under the manifold. If you look straight down along the left edge of the manifold you will see the valve - a black hose with insulation is coming out of it.

 

The Sienna picture above is a good one - use it to find. The valve is to the rear of the engine on the passenger side almost under the manifold. If you look straight down along the left edge of the manifold you will see the valve - a black hose with insulation is coming out of it.

 

After lurking here for months, finally decided to register and post after several DIY's assisted by this site.
Just changed the pcv valve at 127,000 miles. Had my 2005 Rx330 serviced at the dealer for the first 60,000 miles, they never changed it (and perhaps it was fine). I would not have known to change it except for this thread!

compared to the replacement (Lexus genuine), the original appeared to be barely functional.

 

Thanks for the post, pablo87, and welcome to Club Lexus after lurking all this time.

As there is no definitive change interval for a PCV valve on the RX it makes sense that the dealer never changed it out. Unless a CEL comes on or other problem is noted it would more than likely never even be inspected. Back in the day it was a routine item to replace.

I have a replacement PCV valve, NAPA and made of metal not plastic, ready to go when I see the need to replace. Perhaps sooner rather than later.

http://www.napaonline.com/Catalog/Ca...525_0182360673

 

thanks rx330inFl, $6 less than I paid - obviously haven't been lurking enough!!

One thing I didn't do is clean the hose with compressed air, it only dawned on me later. Easy enough to do.

 

The pcv valve is not plastic in my 350.

I was able to remove it and clean it like JGR7 mentioned. Screwed it back in and the vehicle seems peppier.

I'm at 46,000 miles and I'm pretty sure it's never been removed because it was a pita to remove.

I'm going to keep an eye on my fuel usage to see if it made a difference at the pump.

 

R1lee, can you show where the vacuum switching valve PWM is?

 

Hi all,
What does the PCV valve do? What are the signs of bad PCV? Thanks.

 

It allows what gets by the rings to get reburned thru the intake when the valve is open under cruise, light throttle as the valve is operated by vacuum. Idle & heavy throttle the valve is closed as the vacuum drops vs under light throttle w/ high vacuum. IIRC pcv's are required on '67 & newer vehicles. Vehicles had open oil caps & road down draft pipes vs pcv closed systems. When the valve is plugged up w/ oil debris. Yea you can clean it w/ brake clean, carb clean. A shake of the valve & you'll hear the valve rattle like a spray paint can. Really best to just replace it, its not that much vs the time & the cost of a can of brake clean/carb cleaner.