Fault codes on mk4 Golf

[gman3.0]

I have a few problems with my golf so i took it to get the codes read, was wondering if anyone else has had these :

P0102 Air-mass sensor signal too low
P1426 Tank ventilation valve open circiut
0522 CAN message, engine control unit Error in engine control unit

The first 2 codes has made the engine management ligt come on and the 3rd has made the ESP light come on !
These problems happened within 2 days of each other, ive been told there not related.
Any help would be greatly appreciated !

[mluton]

Have you had the codes reset to see if they re-appear.

ESP light is the MAF. Disconnected mine a few times and its come one.

[gman3.0]

Garage has reset the codes and they are gonna test the car tomorrow to see if they reappear.

[gman3.0]

Here's the latest : garage reset codes and only two re-appeared p01102 and 0522, so things pointed towards the MAF being faulty, but they couldnt understand why both ESP and Engine light where both lit!
Anyway after a bit of research i found that, the traction control uses the MAF signal to calculate the engine load, thats why both lights were on. I passed this on to the garage they replaced the MAF, reset the system and now every thing is working as it should (touch wood) !
Thanks mluton for the point in the right direction.