I’m chasing down a lean condition on a ‘05 R53. When I went to check the fuel filter I noticed there was gas pooling in the crevices of the cap on the filter housing. There were also small cracks which I assume is where the leak is coming from. Could this be cause a lean condition? Is the filter downstream or upstream from the pump?

 

As a data point, I had a cracked fuel filter housing that did not result in a check engine light or lean condition. My only issue was the smell of gasoline from the gasoline pooling on top like you describe.

Theoretically, it's possible there could be a fuel delivery issue. I would suggest replace the housing - because leaking gasoline is never good, then evaluate afterward.

 

So many of us have, upon changing out the fuel filter, have gotten a "no start" condition until the fuel filter gasket was properly fitted. I would think that, if there were sufficient leakage, you'd get a similar reaction. Nevertheless, I'd certainly remedy the fuel leakage, especially considering the close proximity of electrical connections.

 

The part has been ordered. Hope this fixes the issue.