Noise from undercarriage

[DanzE90]

hi guys,
I have experience clunking sound from my undercarriage especially during start up or when pressing the accelerator, I thought it was the exhaust heat shield touching the exhaust pipe, but upon inspection it was all fine. When I shaked the middle cat con, the sound sounded familiar, he said that the inside fibre has been broken & needs replacement.

If its true, can I just change to any generic aftermarket cat con, remove it permanently or get a used cat con? or could be other issues? anyone face that issue before?
thanks.

 

[Herbert]

Yes, you are absolutely right on the cat converter. Happened to my e39 (with twin cat converters) and found used one from chop shop for RM1k for a pair. Suggest that you get used one as new one is rather expensive.

 

[DanzE90]

thanks Herbert for the advice, but I don't think I can afford that amount for a used cat con, can I just removed it instead & replace it with a SS pipe?

 

[Herbert]

This subject has been discussed way back in 2009 and check out the following advice from one of our experienced members...


http://www.bmwclubmalaysia.com/forums/forum/the-bmw-range/-3-series/e46/27316-catalytic-converter-removed/page2

10-11-2009, 07:32 PM

Do not remove your catalytic converter....your car will go nuts!

Google: closed loop EFI systems for further clarification

All bmw xhaust systems have been designed, engineered and bench-tested to give your engine the best balance of power, torque and economy.

Aftermarket xhaust only work if you have done internal modifications(pistons, cams, etc) to your engine. Standard engines will receive NO benefits especially if you are running on automatic transmission. You will experience loss of power and increase in fuel consumption.

thanks Herbert for the advice, but I don't think I can afford that amount for a used cat con, can I just removed it instead & replace it with a SS pipe?

 

[DanzE90]

thanks Herbert for the advice.