Strange engine noise

[Luso-Merc]

Hi folks!

I bought a 2003 a while back and have been getting it ready to hit the road this Summer. This one has about 60k miles on it and sat for a few years, as far as I know.

It's pretty much ready, however it's emitting this slight clanking noise from seemingly the bottom end of the engine. It only starts after a few minutes of running, I imagine because the engine oil has warmed up a little and gotten thinner.

I fear it may be related to crankshaft bearing wear, but this car doesn't look like it was beat on at all. I never worked on an issue like this before, so if someone could provide some insights before I have to take it to a shop, it would be very much appreciated. Video of noise in the Google Drive link below (I think it's too big to upload here).

Thank you for your time!

PS: Sorry if I posted the wrong way, this is my first time starting a thread here.

https://drive.google.com/file/d/1pM9...bfSZ11mmP/view

[Meta9]

Pretty commonly reported, do you have Facebook? My Marauder makes the same noise, along with others.

https://www.facebook.com/Light1133/v...ty=10180829124
https://www.facebook.com/groups/1018...9120117344125/
https://www.facebook.com/groups/1018...0289615424125/
https://www.facebook.com/groups/1018...2700485304125/
https://www.facebook.com/SHOdude/vid...ty=10180829124
https://www.facebook.com/armand.shaw...ty=10180829124

There's more on the comments sections of those posts and on youtube.

[Luso-Merc]

Much appreciated! I'll check those links out!

[Mr. Man]

Does it go away when the car warms up? Check the manifolds for leaks if it goes away after it warms up. Could also be related to, as I was once told to me, connecting rod slap. Do you have an engine stethoscope? Could help you narrow down where the noise is coming from.

[Pantera]

Mine has a similar noise (112k miles). On a cold start is fine. But when I drive it and leave it off for about an hour. The cliclk clack starts and goes away in about a minute.

[Luso-Merc]

Does it go away when the car warms up? Check the manifolds for leaks if it goes away after it warms up. Could also be related to, as I was once told to me, connecting rod slap. Do you have an engine stethoscope? Could help you narrow down where the noise is coming from.

Hi Mr. Man,

Thanks for the help on this. To answer your question, the noise volume actually starts to ramp up after a couple of minutes after cold start, (I imagine) because the oil starts to warm up and being thinner.

I do not have an engine stethoscope, but I'll look into it and see what I can find out! This is the first year I got it road-worthy and have driven about 200 miles with no noticable changes in noise/performance, despite having ridden it in different ways, going from cruising to WOT a couple of times.

Thank you very much for your time, y'all!

Have a great week

[Luso-Merc]

Pretty commonly reported, do you have Facebook? My Marauder makes the same noise, along with others.

https://www.facebook.com/Light1133/v...ty=10180829124
https://www.facebook.com/groups/1018...9120117344125/
https://www.facebook.com/groups/1018...0289615424125/
https://www.facebook.com/groups/1018...2700485304125/
https://www.facebook.com/SHOdude/vid...ty=10180829124
https://www.facebook.com/armand.shaw...ty=10180829124

There's more on the comments sections of those posts and on youtube.

Hey Meta9!

Finally got let in that group and I found that my noise is exactly the same as these videos:

https://www.facebook.com/Light1133/v...ty=10180829124
https://www.facebook.com/SHOdude/vid...ty=10180829124

There are varying opinions on what it could be, but the noise I experience is the same one.
As Mr. Man suggested, I'll try to pinpoint it a bit better with an engine stethoscope.

Thanks for the help!

[03Merc]

Cat converter fell apart possibly.


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[Luso-Merc]

Hey folks, hope you've had a great week!

Finally found whatever was vibrating and driving me crazy. It's right behind the oil pan.

https://drive.google.com/file/d/1vuF...pxcFExJz5/view

- Did this part hold any fluids? (I'm not sure what it's called, this is my first RWD car)
- Should I be concerned about any potential damage?
- Does anyone know the sizes of these bolts so I can get new ones. ?

Thanks for the help!

EDIT: I was looking into the service manual and I believe it's the transmission inspection cover! (thank god)

Screenshot below:
Screenshot_20250606_104818_com.google.android.apps.docs.jpg

[Luso-Merc]

Cat converter fell apart possibly.


Sent from my iPhone using Tapatalk Pro

You might be right... I just picked up a rubber mallet, gave them a few hits and you can hear some noise like something's loose inside. The noise isn't from the heat shields, I've given hits while holding the heat shields and it makes the same noise.

What do you think?

https://drive.google.com/file/d/1w5E...HdX33nWt7/view

[03Merc]

Yep, happened to mine on the Crown Vic a couple years ago.


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[Luso-Merc]

Yep, happened to mine on the Crown Vic a couple years ago.


Sent from my iPhone using Tapatalk Pro

Thanks for the help, much appreciated!
Now I'll have to figure something out to replace these (^^)'

I still need to figure out the bolt size for the missing ones in the transmission inspection cover. It doesn't say anything about that in the service manual, just the torque spec unfortunately.