CEL Codes 442 and 422

[60cents]

Just pulled the codes from my 2001 XC70.
P0442 and P0422 were shown.
I'm familiar with them having had them before.
0442 is related to the front O2 sensor I think, which I have replaced recently.
0422 is a small vacuum leak and somewhere on here I read that the problem might be a plugged vacuum line. Perhaps related to the banjo valve on the back of the engine. That's what I remember reading anyway.
There was a diagram of that part that I'm looking for.
Anyone know where it is

[Aviator]

0422 is a small vacuum leak and somewhere on here I read that the problem might be a plugged vacuum line

A plugged vacuum line is not a leak....a hole in a vacuum line is a leak. P0442 code refers to an evap system leak. P0422 refers to main catalyst efficiency which MAY be related to the P0442, but is most likely coming on due to your converter becoming inefficient, or possibly a bad rear O2 sensor.....i.e......no good. Fix the evap system leak first, and see if the other code cycles itself out after a while.

Dave.