gadgetmeister2711

Keep setting these codes:
17831 - Secondary Air Injection System: Bank 1: Insufficient Flow
P1423 - 35-00 - -
17819 - Secondary Air Injection System: Bank 2: Insufficient Flow
P1411 - 35-00 - -
Went through the entire system... Pump runs, vacuum solenoid operates properly, output tests OK, both combi valves open & close, All Vacuum and air lines intact. I'll clear the codes and next cold start, they're back. What does the computer actually monitor to determine air flow? Also had the pump out, the air intake is clean. Thanks for the help.

SweetAudi

yeah I had the same problem....have them do a leak test, and then if that passes, you might have to get a new pump...but in all honesty its just their for emmission purpose, when you start the car up, you can hear the pump turn on, then when the car idles for 40 secs, you can hear it turn off.

Pete0621

Just went through this myself. First be sure that the air pump is working and that hoses (Tubes?) from the air pump to the combi valves are secure. You'll have to wait til morning for a cold start. Open the hood before you start the engine and unhook the power supply to the air pump. As soon as you start the engine (you only have a few seconds to work) connect the electrical connector to the pump and you'll know if it runs. Also be sure that the vacuum hoses to and from the EGR vacuum solenoid are okay. I screwed around with mine for about 4 weeks before I fixed it. The fix in my case was that the connector to the EGR vacuum solenoid valve was not good. The fix was to unhook it and put about 4 twists in the wire before reconnecting it. The EGR vacuum solenoid in located on the top of the engine on the driver side. Remove the small plastic engine cover on that side and you'll see the solenoid. I had to find it the hard way by buying a new one then doing an under the hood comparison. Good luck!

Pete0621

Forgot to mention that mine too tested fine and I wasted nearly $400 at my local shop before I decided to tackle it myself. The 'test' is lame as it may not replicate the real world environment (engine vibration etc.) Try jumping under the hood immediately on cold start to get the real picture. Now I know exactly that it's functioning each morning because I can hear the vacuum cleaner like whine followed by a gulping like sound, and best of all no more 1411 & 1423, and no more check engine light.

gadgetmeister2711

As I said in my original post, everything is working. I can hear and feel the pump running on cold start. I had the vacuum solenoid out and put vacuum directly to the combi valves... they function correctly. All tubing is intact and connected properly.

My pump only runs for about 5-10 seconds on cold start. I'm thinking that the ECM somehow regulates this based on either engine temp or cat temp. If the pump is not running long enough, that could account for the "insufficient flow"????

quickaudi:STFA

I'd say just replace it or find someone local with a known good one and swap.

Pete0621

5-10 seconds is about right. The secondary air supply is brief. Sounds like the solenoid is not working. This is necessary to activate the kombis. Check the electrical connection to the solenoid. Disconnect the electrical connection and squirt some contact cleaner on it, then twist the wire several times before reconnecting it. If that doesn't work, hook up a low voltage LED test light to the connector and see if it lights up on cold start. If it does light then you may have a bad solenoid. I paid about $70.00 for a new one. Not too much to pay to remove it from your suspect list.

S8power

https://forums.audiworld.com/a4/msgs/2657222.phtml

http://www.integrated-engineering.org/catalog/product_info.php?cPath=22&products_id=29

http://www.integrated-engineering.org/catalog/product_info.php?cPath=22&products_id=53

both for 42$ plus shipping cant beat it

01 2.7t

they clog with carbon build up over time, this reduces air flow

Bankser

The dealer wanted $2k for new pump, Kombis, and EGT sensor. They said the pump was bad and handed me the blown 40 amp fuse as proof. As the fuse is the 1st thing to test to see if the pump is shot can someone tell me where the $#%*ing fuse is? Thanks