black smoke at high revs?
Not sure how long my Audi A4 has been like this as I don't thrash it much, it blows black smoke out the exhaust at over 4K revs but doesn't lose power. It is due an oil change and has high miles, I've had the EGR valve, air filter and housing blown through and checked for error codes but nothing :(. I've got 1 week left on the MOT so need to get it sorted ASAP but obviously don't want to be spending £100's getting it sorted because being a 1998 model its just not worth it.
Would be grateful for any ideas on what the problem could be.