DDLexus

great post! Thanks for taking the time and posting pictures too. My California-based car probably need this too.

Slvr surfr

iTrader: (1)

No problem bud! Thanks again for the hint Vcheng!

jayclapp

Slrv surf, thanks for a great post. I never even thought about the sensor having a filter that should have maintenance. I'll definitely do this, as I have noticed that my sensor is also a bit slow in reacting even though I have it set on maximum.

Slvr surfr

iTrader: (1)

Yeah i really dont think this would be a "maintainece" item to Lexus. IMO, i think they would just say its bad a needs replacing. In some cases in an alternator, its just the brushes that needs replacing but most of the time people just replace the whole thing causes its more convienent than rebuilding one rather than replacing the brushes. I guess it depends on the person and how they feel about it.

LS430inDE.

Nice writeup bro...but you should add step 1A - remove wiring harness/connector from sensor. lol

Also, are we 100% sure what you cleaned out is dirt, and not activated charcoal? I'm wondering just how much (black, pebble-like) dirt could become "trapped" in the filter material with the housing sealed up?

If anyone has a parts/service manual, could that filter possibly be a legitimate replacement item, with FRESH activated charcoal?

jayclapp

I'm not real sure, but I thought activated charcoal only became active when it became wet.

It certainly shouldn't be loose and uncontained as shown in the photos I would think.

Do we have a chemist on this forum that can clarify?

AlexusAnja

I'm not a chemist, but an aquarium "expert" of sorts and yes, charcoal is only "active" when exposed with H2O. That's why activated charcoal in the glass jar doesn't go bad. Just like water purification systems that use charcoal for removing the chemical taste.

I don't think the dust in the pictures would be charcoal because why would you want to say 'clean' the air before going into the sensor? The air entering the sensor is not continuing into the vehicle, so pre-cleaning would almost defeat the purpose of it detecting the smog.

caddyowner

^^^ If it is charcoal and it does clean the air, it might be a way to prevent the sensor from activating in conditions that aren't really smoggy. However, following that theory, if the charcoal loses it's effectiveness over time, the sensor should be triggered more frequently rather than less.

Slvr surfr

iTrader: (1)

Oh believe me fellas it was not charcoal. I'm kinda familiar with charcoal myself from the whole home aquarium thing too. This is fine brown dust that got trapped(as designed)in the filter. And yes charcoal do requires water to work is usually used to clean water insted of air. The unit is not completely sealed. There are very small openings at the bottom of the unit that allows just the right amount of air and not a lot of moisture in. Anyway, thanks for adding a extra pov. You really never know about how things are made these days.

LS430inDE.

Interesting perspective of "activated charcoal" in relation to water. Maybe I should have not said "activated"?

The reason I questioned the OP was my experience with NBC MOPP gear (outtergarments/uniforms) that we are issued in the U.S. military (Nuclear, Biological, Chemical Mission Oriented Protective Posture)

Sewn into the inner layer of the garments is literally a layer of charcoal. That charcoal is supposed to help protect the wearer from the nasties of a NBC attack. Whenever we disrobed those garments/uniforms, we had small black pebble-like speckles of carbon on our skin, looking similar to the debris in the OP's photos.

It's also stressed that, once the garments become wet, the protective qualities of the charcoal diminish significantly.

Regardless, sounds as if the unknown foreign debris IS dirt, so.....so much for my hypothesis...lol.

It's not too often I think outside the box..but this was one.

ps...none of this is confidential info

CG lover

did not even know these cars had that feature,, gonna have to take a look at mine ad see if it is in the same location and gently open it up,, sure no harm,,

thanks for the photos and heads up,,

Derry

AlexusAnja

Unless the inside of the housing is super dirty, or the outside is so grummy you want to clean it, you don't even need to disconnect the sensor from the housing. The cover pops out independent of the other half and the connect is not holding the two halves together.

I just cleaned mine for the heck of it (it was pretty dirty actually, although still working) and I only removed the 10mm bolt holding the unit to the car. Then I turned the sensor over, popped the cover off using a screw driver, and cleaned the little filter and reinstalled.

On a side note, I sort of did it this way because I couldn't figure out how to get the wiring harness off... so in reality, a step 1A would be nice. HA HA...

DDLexus

Me too... I spent about 30sec trying to figure out how to disconnect and said, screw it. Didn't need to disconnect anyway.

I also went into the Smog Setting and cranked mine up to HI using the nav screen. I'm tired of smelling the exhaust of old clunkers still cruising these Alabama roads

LS430inDE.

I hear what you're saying, but I believe the OP had pictures with ALL the pieces on a table, disassembled. That wouldn't have been possible had he not disconnected the harness.

adams430

I just did this on my '02. The sensor is bigger and in a different location on mine - it's to the right of the rightmost airhorn. It also has two of those weird sensor things that look like a capacitor with a screen door on top, not one. It's about twice as wide as the sensor pictured here. My filter was filthy.

Like those above me, I could not figure out how to disconnect that beefy plastic electrical connector - it looked like I would need to pry 3 clips up simultaneously to get it off. I think the 01-03 connectors might be different than the one pictured. Anyway, it was easy to clean. The filter was pretty dirty.