# pulled a Code today. Check Engine P0411



## germanengineering g60 (Aug 20, 2007)

so? What could it be?

Audi TT 225q ALMS 
APR stage 1
Bailey DV (keeps getting stuck)
K&N intake
turbo inlet pipe.

ModshackTTuned Induction System
Stage 2
The MOFO with the 4.0 bar


for what I understand with all these upgrades I shouldn't be having a check engine light on.


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## MKllllvr28 (Sep 15, 2005)

Why would it have something to do with your mods? I'd start by checking your vacuum lines. 

16795/*P0411*/001041 - Secondary Air Injection System: Incorrect Flow Detected
*Possible Symptoms*
Malfunction Indicator Light (MIL) ON
*Possible Causes*
Fuel Pump Relay (J17) faulty
Hoses/Pipes to/between Components faulty/clogged
Secondary Air Injection Pump (V101) faulty
Secondary Air Injection Pump Relay (J299) faulty
Secondary Air Injection Solenoid Valve (N112) faulty
*Possible Solutions*
Check Fuel Pump Relay (J17)
Check Hoses/Pipes to/between Components
Check Secondary Air Injection Hoses/Pipes for Carbonization
Check Secondary Air Injection Pump (V101)
Check Secondary Air Injection Pump Relay (J299)
Check Secondary Air Injection Solenoid Valve (N112)


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## TTC2k5 (May 23, 2008)

After you've checked all the vacuum hoses, check the big-a$$ hoses that go into and out of the SAI pump. They become brittle with age and can easily crack (PITA as the must be removed to actually find the cracks). Then, the proper amount of air is not pushed to the combi valve because of leakage. If the combi doesn't get "enough" air, you will get P0411. i did.

solutions: 1. replace hoses => expensive. 2. repair hoses with heat shrinkwrap => cheap.

cheers.


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## germanengineering g60 (Aug 20, 2007)

TTC2k5 said:


> After you've checked all the vacuum hoses, check the big-a$$ hoses that go into and out of the SAI pump. They become brittle with age and can easily crack (PITA as the must be removed to actually find the cracks). Then, the proper amount of air is not pushed to the combi valve because of leakage. If the combi doesn't get "enough" air, you will get P0411. i did.
> 
> solutions: 1. replace hoses => expensive. 2. repair hoses with heat shrinkwrap => cheap.
> 
> cheers.


Whats the "combi valve" ? and where is its location? thanks


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## germanengineering g60 (Aug 20, 2007)

MKllllvr28 said:


> Why would it have something to do with your mods? I'd start by checking your vacuum lines.
> 
> Because Im a bit worried about the modshack maf gig. the maf doesnt have a mesh inside it as the factory one does.


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## TTC2k5 (May 23, 2008)

germanengineering g60 said:


> Whats the "combi valve" ? and where is its location? thanks


Follow the hose from the SAI pump...it connects to the combi. In your pic, I think it's that bright silver/brass/gold looking thingy to the left of the small air filter that you've attached to the hose going into the SAI pump. those are the two ribbed-plastic hoses that crack between the ribs. Also, check the small hoses attached to the combi. actually, you should probably just change them out as they too can cauce problems/crack.


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## ILLA NOIZ (Jul 2, 2007)

I can almost guarantee its not Vac lines (just replaced all of mine) and still have the code. 
- YES - You should check them anyways... as you will see they affect all connections. 

I've already replaced the rivets on one SAI and then replaced the pump and rivets on another... It came back. 

I am planning to replace all the the PCV hoses and Suction Spray Pump located under the intake manifold tomorrow along with the Hockey Puck (Crankcase ventilation pressure control Valve). The diaphram can be damaged on chipped cars and it can get "gunked" upped if the PCV system is allowing oil through the system. I did tons of research and these can cause this code on Audi.

The PCV Valve needs to be replaced as part of maintenance and the hoses and pump will get brittle and crack. The Suction Pump failure can affect braking as well from what I read, as it is connected to the Brake Servo via Vac lines 

The N112 (Secondary Air Injection Valve) can also be defective but is unlikely. (Valve under the intake that connects to Combi Valve and N249 via Vac lines)

I have checked the SAI air lines before - but I may pull them and heat wrap them if this doesn't work. Can't hurt - but not sure I can do this easily at my home without a lift. (don't want to remove belly pan cover without lift... PITA)

Either way... the P0411 Code is a B!TCH. :thumbdown:

Also - I have ordered upgraded silicone pieces from 034 and Forge for the PCV system. I don't want to do this ever again


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## germanengineering g60 (Aug 20, 2007)

how about that black turbo looking thing in the bottom front center of the car? if that has a bad connection, could something go wrong? its connected but it the thing that golds it together is broken. I will go get a new pcv valve right now as I know those need to be replaced regularly and they are cheap to buy.


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## germanengineering g60 (Aug 20, 2007)

TTC2k5 said:


> I think it's that bright silver/brass/gold looking thingy to the left of the small air filter that you've attached to the hose going into the SAI pump.
> 
> is it ok that I put a filter on that hose? that shouldnt make the code right?


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## TTC2k5 (May 23, 2008)

germanengineering g60 said:


> how about that black turbo looking thing in the bottom front center of the car? if that has a bad connection, could something go wrong? its connected but it the thing that golds it together is broken. I will go get a new pcv valve right now as I know those need to be replaced regularly and they are cheap to buy.


black turbo looking is the sai pump.









see link for pics and diy repair if your rivits are toast, which they probably are which will cause the pump to leak and again not push enough air which also = code. repaired and going back in here^^^.

http://wiki.quattroworld.com/index.php/TT.Mk1_SAI_pump_rebuild

cheers


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## germanengineering g60 (Aug 20, 2007)

thanks alot for the infos. so I didnt do anything just cleared the code drove it for a bit and went to pass the deq. passed it, yeey. but I will still get those rivets replaced and just picked up a pcv valve and the piece that it T's in. gonna swap em out right now.

Another PROBLEM that I have is the Bailey DV piston keeps getting stuck in the open. piston is stuck in the cylinder of the DV. it kinda goes sideways n gets stuck. sometimes itll get un stuck for about a minute and itll eventually get stuck again. any suggestions?


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## MKllllvr28 (Sep 15, 2005)

If you've already cleaned and lubed it and the same thing keeps happening... toss it and buy a madmaxx valve.


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## germanengineering g60 (Aug 20, 2007)

changed the pcv valve and the check engine light came back on...

How do I get a hold of madmax to place an order on the dv?


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## germanengineering g60 (Aug 20, 2007)

MKllllvr28 said:


> If you've already cleaned and lubed it and the same thing keeps happening... toss it and buy a madmaxx valve.


what do I lube it with? motor oil?


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