Volvo Repair: replace air pump or valves only?, volvo s70, 1998 volvo s70

Question
I have 1998 Volvo S70 with chk engine andn service lights on, I was advised :
1)you have code for air management system.
2)SES light is on.
3)Another place said I havecode 422 air pump system malfunction and code 446 indicating air pump valve.

A dealership said I need to replace air pump entirely. $750

Another service place said I need to replace valves only. $190 unless they find additional codes.

How do I make sense of this? Your advice greatly appreciated.

Answer
I think the codes are 442 and 446 which are more than likely the valve.the dealer has the ability to activate the pump and check its operation which from these codes is still a possibility but there is usually a 448 code when the pump is bad.



Rege