Recently I looked at a friends B21 rad screen and it was totally blocked, like I have never seen one so bad.
Had him blow it clean and wash it as well.
Based on that finding I pulled his air cleaner and WOW, looked more like 4-5 bird's nests in there.
I wonder how that poor CUT could breathe.
His fuel filter was just as bad.
Needless to say he's deficient in the maintenance department. (but then he is an accountant and counts the pennies)
LOL, his car is the same way.
Your friend should go back to accounting school. Evidently, he missed the section "A penny saved is a penny earned". Neglecting even the simplest maintenance items can lead to spending big bucks on repairs. Hope you "Schooled" him a bit. Friends don't let friends drive dirty.