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That's a code for the secondary air pump system (aka SAIP). There are plenty of things that can cause that but the general operation is that on a cold (but not too cold...) start the ECM will start an air pump for about 60 seconds and add a bit of extra fuel to the mix. The extra fuel goes into the exhaust and the air pump supplies air to the exhaust downstream from the combustion. The injected air burns the fuel and warms up the catalytic converter to make it operational faster. After a few minutes of driving the ECM will run a test on the SAIP to insure that it is working. If that test fails, you get the P0411.

Common sources of problems are a bad SAI pump, a bad SAIP relay, bad SAIP fuse, a stuck combi valve, not enough vacuum to actuate the combi valve, broken pipes between the SAIP and the combi valve.

The SAIP is located down low on the right hand side of the engine bay just behind the grill. After a cold start you should be able to hear it running for 60 seconds or so. I think it only operates in certain temp ranges but as long as the outdoor temp is > 20F and the engine is cold it should run. If it does run, the SAIP and relay and ECM are OK. If it doesn't check those parts.

If the pump runs, then check the piping between the pump and combi valve to make sure it's connected and intact. You can check the operation of the combi valve with a vacuum pump.

Hopefully that's enough to get you started. Search older threads or ask again if you still have questions.
 

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The combi valve runs off of vacuum so no vacuum would stop it from working, but.....I would think you'd have other issues as well if there was a leak that big. But with all the check valves, etc in the system maybe anything is possible. It certainly couldn't hurt to replace that part if it's broken, though.
 

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That's the old style Suction Jet pump. It may not be the cause of the code, but if broken, it needs to be replaced. It is integral to the brake booster system.

 

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2005 Wagon 1.8/tip/4-mo
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Preston - does the tool you use support testing the SAIP and other items? I use VagCom and it does some relay/system tests on the SAIP components including cycling the pump. With all the 1.8t B5.x that have come through our household I would have been lost without VagCom.
 
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