Problem with engine squeeling...

I have a 99 e46 and recently on startup i heard a strange screeching/squeeling noise under the hood. i couldnt identify the issue. the noise got louder wit applied gas. I drive forward a few feet and heard a loud lash in the engine which turned out to me the Protection Cap for the Drive Belt Deflection Pully off and on the floor.

Unfortunately on reverse i rolled over the cap and broke it. Shockingly i throw water in the area the noise was coming from and the noise went away i guess until the belts were dry again.

Checked my Coolant and noticed it was extremely low so i topped it up and preceeded to the mechanic wher i discovered that all the coolant had "Poured out".

The mechanic informed me that the Coolant Expansion tank was leaking the coolant and the noise that i was getting not at the time when i was at the shop, that it is the belts that need changing and the tensioner.

I also discovered that i had an oil leak from the valve cover gasket which MAY have leaked onto the belts.

I am considering DIY for these fixes as his price just for labor alone was rediculous. My main question is, for the noise issue, would it be as simple as replacing the Cap that fell off and how would i know if i really need to change the tensioner?

What is the best order to do these task, cuz it seems like i would be in the hood all day if i choose to DIY. I do street parking unfortunately!!

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This post was auto-generated based upon a question asked on our tech article page here: Pelican Technical Article: BMW Belt Replacement

[Wayne 962]

Lots of stuff here. I can't comment specifically on how long it would take, as I'm not fully aware of your skill level. However, simply replacing the dust cap on the idler pulley will not make the noise go away. It sounds like it's a failing bearing, and you need to spray some WD-40 or similar substance in there to find the source of the squeeling.

- Wayne