Hi guys,

I am try to record and will upload movie clip later.

I have 2004 Mini cooper S with Cosworth header and Borla exhaust.
Also M7 cross bar(under engine and top M7 strut bar as well.

Engine sounds great most of time. No oil leaking and engine oil level is very good and no coolant leak nor error engine code.

Here is what happened.
Some times, (not all time) when I start engine, it sounds like exhaust leaking like sounds(something like head got crack and air leaking like sounds) so engine sounds a lot louder and more like 'CHU, CHU, CHU,...' instead 'Brrrrrrooom'

However, when I drive and passed 2 signal light(like 4 min.), then noise is gone. no noise after that.
I will upload movie clip as soon as I can, but what do you guys think?
Again, no error code nor oil or something leaking.




EDIT -
Ok I took a movie clip today.

First one is normal, second is wrong sound.

this is normal sound(usually)
https://www.youtube.com/watch?v=PLBLKH_1pKY




This is something wrong sound.
Again, if I drove one block, it sounds normal again.
And it happened once in a week.
https://www.youtube.com/watch?v=KmJd-YJuXic



What do you guys think?

 

Uploaded movie clip.

What do you guys think?

Thanks.