Inevitable 3.2l SAIS low flow codes
 

So it finally happened, after 220k km my CEL finally lit up. After some sleuthing with the VAG cable I could see it was showing low flow in the Secondary Air Injection System. Common and known problem with 3.2l engine, and has extended warranty to 190k km. Carbon buildup in SAIS ports. My mechanic says everything else checked out ok (combi valves, air pump, hoses etc.). This is not the usual carbon buildup that happens on the intake side in a bunch of Audi engines, the 3.2 is apparently unique with it's setup for SAIS. Dealer wants $1300 to hook up a glorified pressure washerer and blast the carbon out through the combi valves and into the exhaust. Sounds crazy but I found the dealer instructions and that's essentially the repair. I don't claim to understand the process, it seems to me it would pump water a bunch of places where water shouldn't be, but I didn't study the bulletin in a lot of detail.

I'm not inclined to pay Audi $1300 bucks for a temporary fix to what amounts to a design flaw. Has anyone tried a backyard repair? Maybe take combi valves off and clean mechanically from the outlet side? I think the combi valves are on the back of the engine and a PITA to get to. Taking the exhaust manifolds off would require pulling engine and tranny? Re-flash the ECU to delete the entire system (fine until I have to pass an emissions test)?

Suggestions welcome...

Re: Inevitable 3.2l SAIS low flow codes
 

Had this done under warranty so My two cents not worth your while. However once done trouble free since and that was two years ago.