Swiedeback

Hello. I have a 2011 CT200h. I noticed that after I took the car to have its oil changed, a strange vibrating/hammering sound emanates from the glovebox/behind the a/c vents.

I've done a little research on-line, and I suspect it's because an employee at the oil change place damaged something when checking the air filter.

Does anyone have any advice for me? I'm planning on notifying the oil change place about this problem in person. I've been out of town since the oil change, and today is the first day I can talk to them about. When I do talk to them, I'd like to know exactly what might have happened.

BTW, the noise is there regardless of whether the a/c is set to recirculation or continuous fresh air. And when I turn the heat on, the noise isn't present.

I'm thinking something was damaged when they checked the air filter (as they do as part of the oil change).

Thanks in advance for any help/advice you can give me. The air works, but the noise is super annoying. And since this is a work car, it interferes with calls made on Bluetooth.

roadfrog

When you say "air filter" are you referring to the intake filter or the pollen/cabin filter?

Swiedeback

And thank you for the response.

I meant to describe the the filter inside the glove box in the back of the glove box. The air cabin filter- not the air filter for the engine.

It turns out that the fan below the air cabin filter is unbalanced in some way. I still say may have been caused by the oil change folks, because I had zero issues prior to taking it there for service. And I haven't gone in to that area myself. I rarely go in the glove box at all. Let alone remove panels in it. It would one helluva coincidence otherwise. Right?

Any ideas on what may be causing the imbalance? Seems like it's pretty delicate in that area. The oil change manager did look it over with me, and we couldn't find any debris in the fan area. The filter was very dirty, however. I'm thinking I'll shop vac the fan area soon- just in case something is hiding below the fan that may be causing the imbalance.

When the fan speed goes up, the noise seems to go down. In other words, the higher the revolutions per minute, the less vibration and noise is generated.

As an aside, It seems odd that the area lacks any real housing between the fan assembly and the filter itself. Perhaps that's part of the issue? I'll try to take a picture later and post here.

roadfrog

OK. That's why I asked which filter. I can't remember if it's the same for a CT, but with my LS, you have to ensure that the recirc is on when you change out the filter. If you don't put it on recirc, it screws up the air blend door. Check your manual.

Clutchless

2 possibilities.
1) The cabin air filter should only be inspected/replaced when the system is set to recirculate because otherwise you will disturb the air direction damper when removing it.
2) There is debris in the fan and you vacuum out the cabin filter area. This is common on many cars as it does suck outside air into the car all the time and it could be a stuck twig or other junk.
So set to recirculate, then remove and replace the cabin filter yourself and vacuum out the area while you are doing it and maybe that will fix it.

Swiedeback

Ok. Thanks for the quick responses- and advice. I didn't realize this model had a recirc door- that would certainly explain why something is hung up if the door is broken. Something is clearly rubbing and/or making the fan off balance. I'm assuming now that the recirc door is causing the friction.

Any ideas on where I can get (hopefully free) schematics for that area? It's tough to see down in it, and to get to it physically. I think I've read before where a full repair involves taking the dash out. Major surgery.

Also, it makes the noise whether the air is set to recirc or fresh air intake. And when the heater is on, it doesn't make the same noises.

Clutchless

This parts site from Lexus of South Atlanta has the diagrams http://www.lexussouthatlantaparts.com/