Honda Accord VP, 2002. I use fully sinthetic oil, Mobil 1, 5W-20. How
frequently it should be changed, each 5000 miles or may be somewhat
longer period?

Escape tube is black inside (car has around 50.000 miles, but it was
already slightly black when i bought it used and car had 18,000 miles),
does it means that car burning oil? may be it depend on gas used. I use
87 (manual says 86 or higher).

thanks,

kara