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Hey guys, i’ve been having a little issue with some type of bearing/metal on metal sound in the serpentine belt area. This sound appears when the car has been sitting for over 4 hours and lasts for about 5-10 minutes until it slowly fades away. I’ve changed the belt, tensioner, idle pulley and waterpump. Can it be the crankshaft pulley even if it doesnt make any noises when i only have the AC belt on? Also i have taken the alternator off and spun it with an impact wrench/gun whatever you call it and it was silent. Any input or help would be appreciated!

Heres a clip of the sound:
 

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It’s that critter crawling in your hood! /s

Remove the AC compressor belt and if the noise goes away. If the noise remains remove the main serpentine belt and see if the noise remains. Don’t run the engine for more than 30 seconds! It could be the alternator is the source.
 

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It’s that critter crawling in your hood! /s

Remove the AC compressor belt and if the noise goes away. If the noise remains remove the main serpentine belt and see if the noise remains. Don’t run the engine for more than 30 seconds! It could be the alternator is the source.
When i take the main serpentine belt off, the noise goes away
 

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Likely alternator or water pump shaft. Check each for play.

How old is the water pump?
Neither of them have any play or sounds when spinning them with my hand. And the waterpump is 2 days old. When i replaced it the sound seemed to go away for an hour and then came back. What could cause this?
 

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Im thinking of taking the water pump back to the shop and getting a new one if i just happened to get a bad one.
 

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It is not easy to hear from your video, but it sounds like timing chain to me. It is a bit lose and touches teeth of crankshaft sprocket. It happens when your timing chain wears out and become longer. Tensioner might not do its proper work, so you could try to replace tensioner spring as old one become compressed an a bit short. But it is temporary measure and if it is a chain then you will eventually have to replace it.
In case of timing chain, sound seem to come from front part of engine, but in reality it is under the engine, and it can be heard better if car is on lift or when you listen from outside of a car. You should try any plastic hose one side to your ear another one to engine parts or buy stethoscope.
 

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When i take the main serpentine belt off, the noise goes away
Any change of load changed the tension of a chain and therefore can eliminate sound. Same could happen when your ac engages/disengages. Same when engine heats up, parts expand and sounds disappears. What is the mileage?
 

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It is not easy to hear from your video, but it sounds like timing chain to me. It is a bit lose and touches teeth of crankshaft sprocket. It happens when your timing chain wears out and become longer. Tensioner might not do its proper work, so you could try to replace tensioner spring as old one become compressed an a bit short. But it is temporary measure and if it is a chain then you will eventually have to replace it.
In case of timing chain, sound seem to come from front part of engine, but in reality it is under the engine, and it can be heard better if car is on lift or when you listen from outside of a car. You should try any plastic hose one side to your ear another one to engine parts or buy stethoscope.
Just ordered a new tensioner as you mentioned just in case, since it only cost like 10€. I have tried to locate the sound with an ”poor mans stethoscope” aka a hose, but couldnt really find the source. I have an spare waterpump, alternator and crankshaft pulley also coming in this week, so after installing those, there are 0 old parts in contact with the serpentine belt. Fingers crossed and lets hope for the best! I really hope it isnt the timing belt, since its such a pain in the ass to change.
 

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Any change of load changed the tension of a chain and therefore can eliminate sound. Same could happen when your ac engages/disengages. Same when engine heats up, parts expand and sounds disappears. What is the mileage?
Could be.. It has about 208k miles on it.
 

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Just ordered a new tensioner as you mentioned just in case, since it only cost like 10€. I have tried to locate the sound with an ”poor mans stethoscope” aka a hose, but couldnt really find the source. I have an spare waterpump, alternator and crankshaft pulley also coming in this week, so after installing those, there are 0 old parts in contact with the serpentine belt. Fingers crossed and lets hope for the best! I really hope it isnt the timing belt, since its such a pain in the ass to change.
Not finding a source of a noise pretty much says positive for worn chain. you will hear it clearly when car is lifted and you are under the engine. It is big work but not impossible, hardest part is to remove pulley bolt as you have to keep crankshaft pulley. Rest is all technical. possible to do with engine on car, by removing oil pan and then timing cover.
 

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Not finding a source of a noise pretty much says positive for worn chain. you will hear it clearly when car is lifted and you are under the engine. It is big work but not impossible, hardest part is to remove pulley bolt as you have to keep crankshaft pulley. Rest is all technical. possible to do with engine on car, by removing oil pan and then timing cover.
Yeah, ill return to this thread when my parts arrive and hopefully i will get that noise fixed. If not, i will take it to a shop and let them figure out where the sound is coming from, since i dont have a lift. Might just be the timing chain.
 

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Yeah, ill return to this thread when my parts arrive and hopefully i will get that noise fixed. If not, i will take it to a shop and let them figure out where the sound is coming from, since i dont have a lift. Might just be the timing chain.
Good luck,
but my money is on that chain
 
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