I was doing some cleaning this afternoon and decided to check under the hood. I haven't taken a detailed look under the hood in a while.

Here is a picture of what I saw:


Now here are the areas I was concerned about:


I was really surprised to see what my oil cap power steering reservoir looked like! The dealer changed my oil towards the end of December - would they have left it like this, or did this happen later? Is this normal?

Zoomed in:


And, to add to the surprise, I found this also:

Looks like mice fur...


Looks like mice poopies...

And I don't know what this liquid stain is? Could it be mice pee? Or some spill... maybe an oil spill?


Any thoughts on the oil cap power steering reservoir and liquid stain?

Thanks!

 

You might check/search info on the vacuum pump? It can leak oil and seems to be a common problem on 545's.

 

Sorry... I don't think it's the oil cap... I think that's the power steering reservoir right?

 

Just clean the reseviour off. As far as the other liquid stain, does it smell like anything?

 

I was going to show it to the dealer first before cleaning... although I'm not sure what they would suggest anyway...

The liquid stain has no odor.

 

Its normal for it to "sweat" a little bit, but i do agree that is excessive. The other debris could be anything. I find sand every now and then on my acoustic covers.

 

my 530i does leak also, theres is one solution, replace a reservoir for new one.

 

I would show either show the dealer or clean it off to see if it builds up again then show the dealer. Either way there is one common denominator. Unless of course it does not build up like that again.

 

Mouse piss probably. Like rats, they trickle a lot as a 'path' where they've been. But that could be oil of some sort too.

The goop outside the power steering is probably power steering overflow/leakage mixed with dirt. My power steering reservoir leaks because the o-ring on the lid has been crushed by some ape over tightening it.

 

Thanks for all your suggestions guys.

In December '09, I had the Power Steering warning on my iDrive. I took it to the dealer and they noticed my power steering fluid was too low due to winter / cold-weather contraction. They checked for leakage underbody and found nothing. They topped off the fluid and cleared the warning message - all for a wonderful $149.50. I should have just topped off the fluid myself and see if the warning message would disappear...

Anyway, I'm wondering now if the o-ring got crushed due to over-tightening like or_550i suggested?