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Still can't figure out this noise

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Old 05-01-12 | 06:15 PM
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Default Still can't figure out this noise

I have a better recording of an annoying noise In my 2002 UL that I am having a lot of trouble diagnosing. It's the metallic clinking sound in the first 20 seconds of this video (ignore the keys/key ring jingling). I've had several techs look at it and shake their heads. Heat shields have been removed from the ypipe and it's not corroded. All service done. The noise happens when I'm coasting with my foot slightly on the throttle, but not enough to maintain speed, and is more prominent the faster I'm going. Losing my mind over this, can't believe I'm the only one...


Last edited by ancdmd; 05-01-12 at 06:18 PM.
Old 05-01-12 | 07:47 PM
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Is the central vent set to oscillate? Almost sounds like it's trying to switch back & forth. Give it a look on the climate screen. Good Luck!
Old 05-01-12 | 11:04 PM
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Does it only do it when you're moving?
Old 05-02-12 | 04:21 AM
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I hear the keys rattling but if its that noise from the 7 - 12 second area, that's pretty loud and I'm surprised that it cant be pinpointed.

How's your A/C working (if it was on). I know that the A/C can make a sound similar to that when its low on freon. I had a noise like that on my wifes car that was pretty low on freon. It ended up being a leak so I replaced a couple of parts but the noise it was making was almost a hissing sound but also had a tinny sound. Hard to explain but it stopped when the A/C was recharged.

Good luck it your quest to find the culprit.
Old 05-02-12 | 09:10 AM
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Originally Posted by aqbill
Is the central vent set to oscillate? Almost sounds like it's trying to switch back & forth. Give it a look on the climate screen. Good Luck!
That's not it. It's coming from outside the cabin. My vents are working fine.
Old 05-02-12 | 09:13 AM
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Originally Posted by HiloDB1
Does it only do it when you're moving?
Yes it's only audible when driving @30mph or more, with it being most noticeable at highway speeds. With the car in park or neutral the noise does not occur regardless of engine rpm's.
Old 05-02-12 | 09:17 AM
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Originally Posted by Brewmyown
I hear the keys rattling but if its that noise from the 7 - 12 second area, that's pretty loud and I'm surprised that it cant be pinpointed.

How's your A/C working (if it was on). I know that the A/C can make a sound similar to that when its low on freon. I had a noise like that on my wifes car that was pretty low on freon. It ended up being a leak so I replaced a couple of parts but the noise it was making was almost a hissing sound but also had a tinny sound. Hard to explain but it stopped when the A/C was recharged.

Good luck it your quest to find the culprit.
I am quite familiar with this a/c issue. My car has a very slow refrigerant leak in the evaporator so @ every 6-9 months I get the expansion valve hissing and have to top up the refrigerant. I also replaced the compressor last month because it was locking up at normal refrigerant pressure levels and would only come on if the pressure was lower than normal.

This noise isn't a/c related. It seems to be driveline or exhaust related, but likely driveline.
Old 05-02-12 | 10:42 AM
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Maybe driveline bolts??

https://www.clublexus.com/forums/ls4...nge-bolts.html
Old 05-02-12 | 11:29 AM
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Originally Posted by caddyowner
Hmmm maybe, I'll have to have these checked out. I would think three different mechanics would have checked them but can't assume anything. Thanks for the tip.
Old 03-11-13 | 02:22 PM
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Default great thread

I also have a 2002 with the same issue, did you come up with a resolution..
please let me know if you did
safe driving
Old 03-12-13 | 06:40 AM
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I have not found the source of this noise yet. I thought I had it solved a few months ago, I replaced the worn/broken engine mounts and for a short time the noise wasn't really there, then I noticed it coming back and now its getting louder, but still not as prominent as before. I also had the driveshaft center support bearing replaced, it was squealing badly, so we can rule that part out as the source. I can now hear this noise to some degree constantly and at all speeds, not just on the highway. Here is a clip of how it sounded before I had the engine mounts replaced:


Let me know if you find anything out.
Old 03-12-13 | 08:06 AM
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Default i think

i was hearing a different noise in your video. i have a noise similiar to your s coming behind the ac/vents. i heard thru my research it is possible the servo motors going bad. i got your note about the engine mounts etc.. i guess i mis heard the noise in your video. i was thinking about doing the engine mounts, i heard it helps with the ride being that it takes weight off the front end with new mounts, did you notice that the ride changed with them?
safe driving
Old 03-12-13 | 08:52 AM
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A metallic clinking noise can often times be the strut mounts that have worn out. I can't really tell in your video, but it might be your front strut mounts.
Old 03-12-13 | 02:27 PM
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Originally Posted by BradTank
A metallic clinking noise can often times be the strut mounts that have worn out. I can't really tell in your video, but it might be your front strut mounts.
Strut mounts and all front suspension parts are new.
Old 03-12-13 | 04:08 PM
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Originally Posted by ls430lover
i was hearing a different noise in your video. i have a noise similiar to your s coming behind the ac/vents. i heard thru my research it is possible the servo motors going bad. i got your note about the engine mounts etc.. i guess i mis heard the noise in your video. i was thinking about doing the engine mounts, i heard it helps with the ride being that it takes weight off the front end with new mounts, did you notice that the ride changed with them?
safe driving
I don't recall much improvement in the ride, but I did notice and improvement in the way the car drove, it runs smoother and there's no shaking at startup or with heavy throttle. Conceivably the car will roll smoother since the motor isnt bouncing around. Definitely a must-do item (motor mounts) after 100k miles I'd say.


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