Belts

There is a TSB for the belt noise. The mechanical belt tensioner has to be replaced with the updated hydraulic ones. The water leak has to be diagnosed. Have you seen any wet spots around the sunroof? Some 3 series had problems with the windshield not being sealed correctly. I'd suggest to find a good BMW independent shop in your area and ask them to diagnose it. Here is the TSB (SIB): Engine - Screeching Noise On Cold Start Up SI B 11 04 03 Engine February 2007 Technical Service This Service Information bulletin supersedes S.I. B11 04 03 dated July 2005. [NEW] designates changes to this revision SUBJECT NEW Noise Complaints From Mechanical Alternator Belt Tensioners MODEL E39 5 Series and E36 Z3 with M54 engine through end of production E60 5 Series and E83 X3 with the M54 engine through current production E53 X5 through with the M54 engine through 05/04 production E46 3 Series with the M54 engine through 5/04 production [NEW] SITUATION Customer complains of the rattling or screeching noises upon cold start of the engine. The noise will usually dissipate after the engine warms up. Cold weather aggravates the condition. Noise comes from the area of a mechanical alternator belt tensioner. CORRECTION ON A CUSTOMER COMPLAINT BASIS ONLY, and only after the original mechanical belt tensioner in the vehicle has failed, replace the mechanical tensioner with the hydraulic style tensioner and install a new Ribbed V-Belt. Zee