Hello

I bought a 2004 volvo xc90 in march from a private owner 180 miles on it i thought the only thing i had to fix was the control arm that was $500 off the rip at a volvo dealer ok not bad but then it was a power steering leak that at first wasnt so bad but got worse to where it leak so much it got into the altenator and i had to have that replace thank god my step dad is some what of an mechanic found some cheap used parts and fixed both problems not noticing and oil leak from engine it looks like so i been making sure i put oil in keeping it full one day driving to work i stop at a red light proceed to acclerate here a thud and then car gets real shaky and less power go to auto zone and they give me codes p0016, p0017, p0497, p2406 did some research and it sounds like its the camshaft or timing belt is there any more suggestion anyone can give so that i can let my step dad know and maybe he can fix or maybe i might have to sell it i cant really afford a pricey shop to put it in i really like the car first time for me of having something a lil nice but on the other hand it still drives i drive it to work every day it just seems like it needs a tune up to me but with those codes i know thats not the case.