MarkFank

Over the weekend I was on a road trip & my oil "MIN" warning light kept coming on but there is plenty of oil. Called dealer & they think it is a faulty sensor. When I got home I checked for DTCs and this was there:

17831 - Sec. Air Inj. Sys, Bank 1, Flow too Low
35-10 --- Intermittent

Could these be related? TIA

Auto Union Jack

Leaky bypass valve. Change to 110s and watch it vanish.

Brian-PA

is this a part that I can get directly from dealer service? When I take my car in for the 5K service I would like to have this change done. I am working on negotiating free labor (partial) to install a brake upgrade during the same service visit. (They are swapping them out anyway)

TIA (again).

Auto Union Jack

It is a Bosch, but not Audi part. It is the same part# as an MTM/Bosch Sport valve. Hope that helps.

GmbHouse

Do I understand? The MTM/Bosch Sport valves are 996TT valves? Thanks.

Brian-PA

got it. Thanks. I'll save it this time.

Auto Union Jack

reported as such on the S4 Forum.

MP4.2+6.0

I got the same sec. air inj sys flow too low message when my check engine light came on last weekend on a 4.2. Cleared the code, but then it came back later again. After looking at the CD ROM parade of horribles, I located the check valve as being under the center engine cover. As soon as I removed it, I saw the vacuum hose was loose to the valve. Turned out the 10-12" hose shrank over time by an inch or more. Put on a new piece of vacuum hose, reset the light and no more problem; the slightly rough engine I felt for a while before was gone too. End of problem.

Auto Union Jack

<center><img src="http://pictureposter.audiworld.com/13568/vaccuumdiagram2.7.jpg"></center><p>- To reservoir under right front wheel housing shell.
2 - Air cleaner
3 - Mass Air Flow (MAF) sensor
4 - Evaporative Emission (EVAP) canister
5 - Turbocharger engine bank 1
6 - Combination valve for secondary air injection (AIR)
7 - Secondary Air Injection (AIR) solenoid valve -N112-
8 - Wastegate bypass regulator valve -N75




--------------------------------------------------------------------------------

10-36


9 - Check valve for crankcase ventilation
10 - Collector housing for crankcase ventilation
11 - To power brake booster
12 - Check valve (arrow indicates direction of flow through valve)
13 - Secondary Air Injection (AIR) pump motor -V101-
14 - Vacuum limiter valve
15 - Fuel pressure regulator




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10-37


16 - To Leak Detection Pump (LDP) -V144-
17 - Vacuum reservoir
18 - Turbocharger engine bank 2
19 - Pressure unit for charge air pressure regulation
20 - Combination valve for secondary air injection (AIR)
21 - Check valve (arrow indicates direction of flow through valve)
22 - Charge air pressure cooler engine bank 2
23 - Pressure hose engine bank 2




--------------------------------------------------------------------------------

10-38


24 - Recirculating valve for turbocharger -N249-
25 - Cut-out valve (mechanical circulation valve)
26 - Connection hose
27 - Pressure line engine bank 2
28 - Connection hose
for both charge air coolers
29 - Check valve for crankcase ventilation
30 - Connection hose




--------------------------------------------------------------------------------

10-39


31 - Cut-out valve (mechanical circulation valve)
32 - Pressure line engine bank 1
33 - Pressure hose engine bank 1
34 - Check valve (arrow indicates direction of flow through valve)
35 - Evaporative Emission (EVAP) canister purge regulator valve -N80-
36 - Charge air pressure cooler engine bank 1
37 - Pressure unit for charge air pressure regulation




--------------------------------------------------------------------------------

Auto Union Jack

<center><img src="http://pictureposter.audiworld.com/13568/2.7overview.jpg"></center><p>
BPVs bilaterally adjacent to #22.