bearing / noise when idling or driving

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whizbala

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Hello -
i purchased a 2018 Expedition with 106k last weekend, and getting started with all the fixes needed. I am unable to diagnose this rattling sound from the front of the car. the pitch does increase with RPM.

Appreciate the help.



Thanks
Balaji
 

Mr Big

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Hello -
i purchased a 2018 Expedition with 106k last weekend, and getting started with all the fixes needed. I am unable to diagnose this rattling sound from the front of the car. the pitch does increase with RPM.

Appreciate the help.



Thanks
Balaji
Turbos or turbo waste gates?
 

Rednecked

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Hello -
i purchased a 2018 Expedition with 106k last weekend, and getting started with all the fixes needed. I am unable to diagnose this rattling sound from the front of the car. the pitch does increase with RPM.

Appreciate the help.



Thanks
Balaji
Kinda sounds like the AC clutch or a bad pulley bearing Did you try it with your AC off?
 

Ugh_J

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That's something the serpentine belt attaches to. Best advice: get a 3-4ft length of 1/2" tubing of some sort (preferably clear, IYKYK), hold one end to your ear and stick the other end down by the pulleys the belt runs over (carefully lol). It'll work like a stethoscope and let you key in on where the noise is coming from.
 

SyndicateZ

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I have the exact same sound coming from the front area of engine when it starts cold in the winter, but goes away after a few moments. Dealer couldn't replicate it and sent me on my way (because I have warranty)
 

Mr Big

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I have the exact same sound coming from the front area of engine when it starts cold in the winter, but goes away after a few moments. Dealer couldn't replicate it and sent me on my way (because I have warranty)
The common rattle noise under hood when engine is cold usually comes from cam phaser noise or turbo waste gates. Once the engine heats up the noise usually goes away. From another post: "If the rattle is harsh and goes away after 2-3 seconds, it's cam phasers. If it is softer and lasts for 60-120 seconds, it's wastegates".
 

SyndicateZ

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The common rattle noise under hood when engine is cold usually comes from cam phaser noise or turbo waste gates. Once the engine heats up the noise usually goes away. From another post: "If the rattle is harsh and goes away after 2-3 seconds, it's cam phasers. If it is softer and lasts for 60-120 seconds, it's wastegates".
I also get the wastegate rattle that you speak of (which never goes away) . My cam phasers dont rattle as those were replaced 20,000 miles ago. The sound in the video is NOT wastegate or cam phasers rattle . It's definitely serpatine drive belt driven. Like a belt tensioner or ac clutch bearing related..Also, wastegate rattle is more pronounced from the wheelwells and not from the front of the engine.
 
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Mr Big

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I also get the wastegate rattle that you speak of (which never goes away) . My cam phasers dont rattle as those were replaced 20,000 miles ago. The sound in the video is NOT wastegate or cam phasers rattle . It's definitely serpatine drive belt driven. Like a belt tensioner or ac clutch bearing related..Also, wastegate rattle is more pronounced from the wheelwells and not from the front of the engine.
Yea, I didn't look at the video until now. You're right, that's an idler pulley or AC clutch, making that noise, depending on where the noise is coming from.
 
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