Alright Guys, i need your 2 cents again.

My 04 530i has 42k miles on it now, and has some issues, i was hoping you guys could possibly help me out in identifying these problems

1) Theres a squeeling/whistling sound coming from the engine when the car is in gear. Its gotten louder and louder over time. I had a someone look at it and they said its probably the tension belt, and they have to put in a new hydraulic piece to fix it....does that make sense?

2) When driving over bumps/potholes a rattling noise is coming from underneath the car. It's a coming from the driver side, but near the back. Its a very weird sound, and i only hear it when i go over something...it sounds as though something is loose and shaking around under there. Ive had a look and cannot see anything so im confused as to what it might be.

If you guys recognize this problem, do let me know.

Lastly, last time i had a sensor issue and BMW of Fairax charged me $1800 to fix. I want to avoid going there again and would like to try a private shop if possible. If anyone from the Washington DC area knows a good and cheaper place to take Bimmers for repair, please let me know.

Thanks in advance!

Don't know about any of your problems but the first one...

Just had the same problem fixed on my 04 530i -- tensioner pulley had to be replaced along with the other pulley the belt is attached to...

Apparently our 04's have a mechanic tensioner vs. new BMWs have a different piston/spring based tensioner...i'd get it fixed/looked at ASAP because if it breaks it can cause other problems.

If you're Northern VA you should look up Martin Motorsports -- tell him Shea reccommended you -- he's a great mechanic, fair and does the job right

The rattling might just be the heat shield. I know mine was bent a bit and was rattling (could hear it clearly at a drive-up window). It just needs to be bent back - you can do it or any muffler shop should do this for FREE. Good luck!