Secondary Air Injection System

Been having problems recently, VAG-COM pulls up the following:-

17831 - Secondary Air Injection System; Bank 1: Insufficient Flow P1423 - 35-00

17819 - Secondary Air Injection System; Bank 2: Insufficient Flow P1411 - 35-00

That was after I noticed the engine light on a few days back.

Then this morning on my way back south, just cruising along at 75, suddenly all power cut, ABS light on, EPC light on and for the next 60 miles it wouldn't accelerate up any form of incline, only on declines and not with full power.

Got to work, checked it out with VAG-COM, same code 17831 amongst others from the ABS saying problem from throttle position sensor. I think the TPS and ABS problems came as a result of driving after the 17831/17819 codes.

Reading up on the codes at the Ross-Tech wiki, does anybody know where to look for this secondary air injection pump and the valves associated with it, as I'll have to check the pipes over to start with - this is the problem that has been causing the little hesitation changing gear and at about 3500-4000rpm under load I think.

Any help finding the pump/valves/pipes much appreciated

Ah, found some diagrams on VagCat, no worries chaps