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Smog sensor AUTO Function (recirculate button) wakes up slowly...

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Old Jul 13, 2021 | 05:59 AM
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Question Smog sensor AUTO Function (recirculate button) wakes up slowly...

Hello Lexus friends.

My auto function (button of the recirculate) doesn't work directly. The button is always responsive but the problem is that when I put it in auto it stays on recirculate for a long time... when I play with it a few times and push some other buttons it starts to work and it starts to detect smog in the air.

I know about the secret setting but even in the lightest possible position its still really slow and it can take up to 10 minutes before the smogsensor starts working.

I already cleaned the piece of cotton in the sensor element behind the grill but that didn't do the trick. Maybe even made it worse. I used alcohol and that white piece of cotton was full of dust and crap.

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Old Jul 14, 2021 | 10:36 AM
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Did you actually clean the sensor too, not just the cotton filter? If not, try cleaning the sensor below the cotton filter. A Q-tip and some sensor cleaner (MAF or maybe even alchohol) on the sensor surface might clear up your issue. When I did my filter cleaning I just used plain water and let it dry.
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Old Jul 14, 2021 | 11:48 AM
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Originally Posted by TominPT
Did you actually clean the sensor too, not just the cotton filter? If not, try cleaning the sensor below the cotton filter. A Q-tip and some sensor cleaner (MAF or maybe even alchohol) on the sensor surface might clear up your issue. When I did my filter cleaning I just used plain water and let it dry.
Good point! I have cleaned that sensor with the same MAF cleaning stuff because I was afraid of breaking it.

My GS300 has the auto function as well and that doesn't work either but that one really isnt working... I am really disappointed about that
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Old Jul 15, 2021 | 04:02 AM
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Guys, is it possible that my LS came without a smog sensor? I didn't find it and it's wires. (searched intensively)
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Old Jul 15, 2021 | 05:33 AM
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Originally Posted by beercan
Guys, is it possible that my LS came without a smog sensor? I didn't find it and it's wires. (searched intensively)
I cant believe this. You must have an auto button within the recycle button.
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Old Jul 15, 2021 | 06:50 AM
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beeercan, open the hood and post a photo or two of the front of the radiator in the region around the two horns..
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Old Jul 20, 2021 | 12:20 PM
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Originally Posted by TominPT
beeercan, open the hood and post a photo or two of the front of the radiator in the region around the two horns..
and I don't see any wires.

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Old Jul 20, 2021 | 12:28 PM
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Originally Posted by beercan
and I don't see any wires.
It looks that I have some good news and some bad news. The good is that you do have a smog sensor. The bad is that some bastard took it away. The wire you see (The fat one) must end in a plug and thats where your smog sensor should connect.

Check added pic


Last edited by NLLex; Jul 20, 2021 at 12:32 PM.
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Old Jul 20, 2021 | 12:30 PM
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.............
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Old Jul 20, 2021 | 12:31 PM
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It ain't there. However, there is a small hole in the radiator support. left hand side, visible in your photo to the left of the passenger side horn, which is where on my car the smog sensor bolts to the radiator support. I think someone may have removed the smog sensor from you vehicle in the past, for some reason. That hole, to the right of the other larger hole, is for the bolt attaching the smog sensor.
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Old Jul 20, 2021 | 01:59 PM
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Originally Posted by TominPT
It ain't there. However, there is a small hole in the radiator support. left hand side, visible in your photo to the left of the passenger side horn, which is where on my car the smog sensor bolts to the radiator support. I think someone may have removed the smog sensor from you vehicle in the past, for some reason. That hole, to the right of the other larger hole, is for the bolt attaching the smog sensor.
Yes, I think it had to be here. But I don't see any wires coming to it and don't know where it has to originate.
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