I have a 1999 S80 T6 with the p0171 and p1171 lean trim codes and idles rough. If I clear the codes the car idles great for a little while. When the codes come back it idles rough and lightly puffs black smoke.

So I believe a canister purge valve and perhaps a maf (I've had maf symptoms in the past)

Can some one check my work, and recommend a place to order these parts

Also I heard some stuff about there being multiple part numbers for the MAF, what should I be looking for?