2 questions

2 I took the throttle body of to clean it and the lower bolt on the passenger side was covered in oil, where good it have come from?
Also, the whole inside of the intake is caked with corbon buildup, is there a way to get in there and clean it?
Thanks!!
2) oil? that's odd. Clean it. Someone may have oiled it for installation.
The caked on carbon is caused by the EGR. the loose stuff can be cleaned off with carb cleaner. the rest would require work.

So what standard size would fit, that is one that is inbetween a M8 and a M7?
Thanks







