Audi S7 AIR Issue

Craig Owner California Posted   Latest  
2013 Audi S7 4.0L (CEUC) 7-spd (0B5) — WAU32AFC1DN100032
P0491 — AIR System Insufficient Flow Bank 1
P0492 — AIR System Insufficient Flow Bank 2

Hello, Trying to figure out this Audi with Service Information I cannot find. Looking for specific data- what solenoid performs what and when. The system is very complex and all components either require front clip removal(which we did) or dropping the engine to get to the Secondary Air solenoids. The issue I am having is I am only getting 5 inches of vacuum to the combo valves which allows air flow into the heads, When I artificially boost the vacuum to 7in. the valves open and allow air flow, The low vacuum signal is resulting in insufficient air flow codes. I am loosing vacuum but don't know where. Hard to see anything on vehicle. When I apply smoke to the control circuit, smoke does come out the vent which i assume they use to dump air to deactivate the system. (Audi calls this a water separator). Again I assume this is normal but with no information other than basic theory they provide, I cannot figure out system.

Hans Diagnostician

This is about all I have at the moment, SAI is on page 80 of the pdf. Maybe work backwards from the vacuum pump to see were the pressure drop is? I don't get those in often, so I don't have any specifics yet.

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Anthony Technical Support Specialist

Hi Craig: Have you looked to see if TIB … applies? The vehicle is a 4GA. Use an A7 with your engine and trans options for service information lookup. HTH, Guido

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