" Permanent" "Second" Engine Air Filter???
Thread Starter
3rd Gear
Joined: Jan 2024
Posts: 3
Likes: 0
From: Georgia
" Permanent" "Second" Engine Air Filter???
Hey guys, I was changing out the engine air filter on a friend's 2015 RX350 and noticed what looks like a second "permanent" air filter installed in the back of the air cleaner assembly. I'm not a mechanic but have been working on cars for years and have never seen one of these before. The car has about 140,000 miles on it and it looks pretty dirty, and they mentioned their gas mileage recently as started to deteriate. I've checked the tire pressures, changed the spark plugs about 50,000 miles ago and changed the air filter. Is there any way to replace this other "filter" or clean it? I've looked all over the internet and the forums and part diagrams and I can't find anything mentioning this other "filter". Thanks for any info!!
Instructor
Joined: Nov 2015
Posts: 1,048
Likes: 351
From: Atlanta, Georgia
Thread Starter
3rd Gear
Joined: Jan 2024
Posts: 3
Likes: 0
From: Georgia
To my understanding. That is a charcoal filter media that absorb fuel emissions that may be sucked back into the engine. Basically an emission control filter. Some owners remove them for better performance in various models from all brands that has the built-in filter.
https://www.youtube.com/watch?v=F1JmOKKAgyQ&t=1s
https://www.youtube.com/watch?v=F1JmOKKAgyQ&t=1s
Trending Topics
Pit Crew
Joined: Mar 2018
Posts: 199
Likes: 59
From: AZ
After watching some videos of this "filter" it has become clear what the original(C.A.R.B.) intent of this was(is). It's not really cleanable for one thing. And a dyno test that compared with & without it on a 4-cyl. showed about ~4-5 H.P, gain without it. Sooo...?
ClubLexus Stories
Celebrating Lexus & Toyota from Around the Globe
Top 10 Lexus & Toyotas to Drive Before You Die!
Joe Kucinski
Top 10 Lexus/Toyotas With The LEAST 5-Year Depreciation
Joe Kucinski
Lexus LC500 Convertible Auction: A Preview of Rising Values?
Brett Foote
GX 550 vs TX 550: Best 3-Row Luxury Lexus Family Hauler
Michael S. Palmer
9 Best Lexus Models You Can Buy for Half Price (And 1 You Shouldn't!)
Joe Kucinski
2026 Lexus NX Buyer's Guide: Models, Features, Prices & More!
Brett Foote
Top 10 Reasons to Buy a Lexus TX 550h+ (& 3 Reasons to AVOID!)
Michael S. Palmer
Top 10 Lexus & Toyota Models of the 1990s RANKED!
Joe Kucinski
10 Great Toyotas That Could Have Been Lexus Models
Joe Kucinski
Instructor
Joined: Nov 2015
Posts: 1,048
Likes: 351
From: Atlanta, Georgia
LOL. I was considering removing the emission filter when I lasted changed my air filter, but I really do not care about increasing HP in my RX350 to go through the trouble.
Thread
Thread Starter
Forum
Replies
Last Post
LexusGuy01
GS - 4th Gen (2013-2020)
40
Nov 14, 2020 11:17 AM