Secondary Air Injection Port Cleaning

[Culi]

Dealer is asking for $2k to do the secondary port cleaning since I'm outside of 120K miles warranty.

Has anybody try to clean the secondary air injection ports at home? I was wondering how much of the front end you need to take off to access the ports. My guess is the bumper, radiator, radiator fan, exhaust manifolds and combi valves need to be removed. There are two videos that show where the port is located and how to clean them, but it also show the entire front end removed. I don't think the entire front end needs to be remove.

https://www.youtube.com/watch?v=ZivHxigu854

https://www.youtube.com/watch?v=zVN1-4ZvCII

[Snowmonkey]

I have been running into this problem a lot lately, ill clear the code and it comes right back.

When i asked Audi of America about the TSB, being under the mileage and age limit, they responded and said the only thing covered under the TSB is faulty valves or the pump. Nothing about the cleaning being covered.

Has anyone found a way around this issue other than having it cleaned? Is there a way to bypass the exhaust flanges somehow to keep the system from getting too clogged up?

[chilort]

I have been running into this problem a lot lately, ill clear the code and it comes right back.

When i asked Audi of America about the TSB, being under the mileage and age limit, they responded and said the only thing covered under the TSB is faulty valves or the pump. Nothing about the cleaning being covered.

Has anyone found a way around this issue other than having it cleaned? Is there a way to bypass the exhaust flanges somehow to keep the system from getting too clogged up?

The secondary air is covered. Contact AoA if the local dealer won't play ball. Warranty goes out to 120,000 miles.

[Culi]

I'm curious if this is a straight forward DIY. Removing radiator and manifold is probably a big job, but since i have not done it myself I'm not sure.

[Snowmonkey]

The secondary air is covered. Contact AoA if the local dealer won't play ball. Warranty goes out to 120,000 miles.

I did contact AoA about it, that was their response. Dealer said I need to get confirmation from AoA since they had never done this particular TSB (somehow?) so that's why i reached out to them in the first place.

Thank you for contacting Audi of America regarding your beautiful 2013 Audi S4. I understand your
concern for the check engine light that gave a fault that may be in relation to the P0491 Secondary Air
Injection System.
I see here that you have warranty extensions specific to your vehicle, the Secondary Air Change Over
Valve and the Natural Valve Leak Detection Switch. Both of these concerns have extended warranties of
10 years or 120,000 miles.
We advise to have your vehicle diagnosed at an authorized Audi dealership. If the Secondary Air Change
Over Valve is the diagnosis, warranty coverage will be offered.

I sent that to the dealer and they agreed that cleaning would not be covered. I responded to AoA with a copy of a letter sent to another owner that DID mention cleaning would be covered and they said I needed my own copy of the letter, which i don't have since I am the second owner of the car.

[Snowmonkey]

I'm curious if this is a straight forward DIY. Removing radiator and manifold is probably a big job, but since i have not done it myself I'm not sure.

Im sifting through the service and repair manual, ill definitely keep you updated if i find anything usefull.

[Culi]

Im sifting through the service and repair manual, ill definitely keep you updated if i find anything usefull.

I was skimming through it to. The AC condenser needs to be removed also. I don't think we are allow to vent refrigerant into the air. Might need special machine for this.

[Snowmonkey]

I was skimming through it to. The AC condenser needs to be removed also. I don't think we are allow to vent refrigerant into the air. Might need special machine for this.

You can get the valves and stuff necessary to do it yourself for less than 50 bucks. Or know someone in the HVAC industry who you can bribe with a case of beer to come help out.

[grat_master]

go to another dealer. problem solved.

[Culi]

go to another dealer. problem solved.

True, but I just like to tinker and learn how to do stuff.

[cspcrx]

If your flagged TD1 they will deny it, not sure if you are.

[Snowmonkey]

go to another dealer. problem solved.

Do you know of any documentation i can produce that would help my case? other than the TSB, which the first dealer pretty much ignored.

[SebR]

TSB does cover it, though you need the code on Bank 1 and Bank 2.

[Culi]

Guys, we understand that there is a TSB that covers the carbon cleaning up to 120K miles. The reason I created this thread is to see if we can have a DIY or suggestion on how to fix this ourselves without going through the dealer when the car is outside of warranty. This seems to be common and occurs maybe every 50K miles...?

I have been thinking that maybe removing the exhaust manifold and combination valves only. This provides access to the secondary port from the back side at the combination valve attachment. Stick a pipe cleaner / flexible drill bit into the hole and try to get the carbon out that way. Put a stop or something to block the freeze plug from falling out the opposite end. This could save time since the front end doesn't have to be removed.

[Snowmonkey]

Guys, we understand that there is a TSB that covers the carbon cleaning up to 120K miles. The reason I created this thread is to see if we can have a DIY or suggestion on how to fix this ourselves without going through the dealer when the car is outside of warranty. This seems to be common and occurs maybe every 50K miles...?

I have been thinking that maybe removing the exhaust manifold and combination valves only. This provides access to the secondary port from the back side at the combination valve attachment. Stick a pipe cleaner / flexible drill bit into the hole and try to get the carbon out that way. Put a stop or something to block the freeze plug from falling out the opposite end. This could save time since the front end doesn't have to be removed.

Sorry, i inadvertently hijacked the thread.

Going in from the back sounds tricky though. If you were really set on DIY, you could always just completely cut out the ports in the engine block and tap directly into the manifolds with a stand alone secondary manifold. Plug both sides of the engine block ports and run the combi valves into new tubes running along side. That would sure make cleanout easier in the future, if you so chose. Someone more familiar with these engines and working on them should chime in and tell me if I'm being stupid, but I don't see any major obstacles to that method.

[Culi]

I'm reading through the Sevice Bulletin for port cleaning. The dealer uses specialize nozzle to clean the port. There are two high pressure water nozzles that are being used and a special adapter for cleaning the side port; one nozzle for cleaning straight down the port, and one with a scale to clean the three side ports. The adapter is used for cleaning the side port. Here is the tool price.

https://www.ecstuning.com/b-genuine-...l/vas6825~oev/

As far as the procedure goes, the car is put in service position, disconnect the exhaust between the first and second muffler, remove spark plugs and cover the coil electrical end. The belts, front hard coolant hose, the coolant flange, and the vertical coolant hoses that goes into the supercharger need to be removed. After that, remove the freeze plug and attach the adapter. Connect the hose to pressure washer and stick in the nozzle that clean at 2000 psi. Run it all the way to the combi valve. Change nozzle for cleaning side port. There is a predetermined length for each side port. After cleaning, suck any water that is in the combustion chamber by using a vacuum hose through the spark plug tube.

https://static.nhtsa.gov/odi/tsbs/20...53120-9999.pdf

Procedure seems straight forward. Just the price of the tool is expensive. Wonder is anybody is renting out that tool.

[cspcrx]

I spoke to a couple of guys I know that own shops, ex Audi techs, and they all told me they would not attempt the service as special tools are needed. Doesn't mean others wouldn't but seems like its not something they have access to or are willing to tackle.

[Culi]

I guess the special tool is the water pressure nozzles. I'm debating on buying the tool and still save $1000, or do it the manual way as shown in the videos in the original post. The removal of the whole front end is a little scary, but just a little more work after putting the car in the service position. Just disconnect some coolant hoses, AC lines, hood pull cable, and some electrical. Probably not as easy as I think, but shouldn't be that complicated right?

Anybody Audi tech on this forum want to chime in?

[thaifoodninja]

Make sure all water is removed from the combustion chambers by using the self-start function twice while the spark plugs are still removed (cover spark plug openings with a towel). Install spark plugs and coils.

Part of that service expects water to get into the cylinder. That's my butt pucker, nope I'm out moment.

[Culi]

Haha me too bud. You are spraying high pressure water into the port that connects to the exhaust, which connects to the chamber. Either that or using a drill bit to clean out the carbon.

[Snowmonkey]

Haha me too bud. You are spraying high pressure water into the port that connects to the exhaust, which connects to the chamber. Either that or using a drill bit to clean out the carbon.

Yeah, thats gonna be a no from me dawg. Sheesh, that sounds sketch.

Does anyone know the consistency of the carbon deposits? Are they pretty easy to break down or are they hard as rock? Could some sort of increasing size of wire brush setup work to gently brush it all out? Hell, even custom grinding some sort of drill bit thats more for rock, doesnt have sharp corners that could scratch the walls of the manifold, would be a helluva cheaper option than that specialized tool.

[Culi]

Probably the same consistency as the carbon on the valve. That is very easy to remove. The video said to use the drill bit and turn it by hand. So I assume it is very soft, but sticky.

[Snowmonkey]

Probably the same consistency as the carbon on the valve. That is very easy to remove. The video said to use the drill bit and turn it by hand. So I assume it is very soft, but sticky.

I'm imagining it like built up soot in a chimney, so a wire brush pipe-cleaner is probably a good option if you're worried about the drill bit. Probably wont leave the ports as shiny clean as the 2000psi pressure washer that Audi recommends but it will be a damn sight cheaper, and you don't have to worry about water in your cylinders.

[JS81]

What about deleting the system and coding it out?

034 has a delete for previous years. Perhaps they would be willing to do one for the B8, and offer off menu coding.

[Culi]

What about deleting the system and coding it out?

034 has a delete for previous years. Perhaps they would be willing to do one for the B8, and offer off menu coding.

You're telling me that you can delete the coding for this and the error will not pop up again? I thought it was required for emission. The only reason I need to get this fix is because I can't pass inspection and get my car registration renewal.

[JS81]

No idea if its possible on our Simos, but it appears it could be coded out on previous platforms.

[Snowmonkey]

No idea if its possible on our Simos, but it appears it could be coded out on previous platforms.

From talking to my mechanic (not Audi dealer, just German specialist), he mentioned that since it is emissions related, it is buried deeeeeeep within the coding, and isnt just based in the ECU like it used to be. That's probably why previous gens were able to be tuned out. As far as he had heard, there was no way to code out the SAI system without major major electronics reworks

[thaifoodninja]

From talking to my mechanic (not Audi dealer, just German specialist), he mentioned that since it is emissions related, it is buried deeeeeeep within the coding, and isnt just based in the ECU like it used to be. That's probably why previous gens were able to be tuned out. As far as he had heard, there was no way to code out the SAI system without major major electronics reworks

Yep, the whole ECU tune needs to support it, not just doing a simple delete of hardware with a blockoff plate. the ecu reads the difference between the precat o2 while the SAI system is requested on vs off. Being that with the SAI flow on, it will expect to read leaner in the precat o2 than when off since the SAI airflow is meant to bypass combustion. It will cycle it specifically for testing briefly while driving during the first 100 miles or so, not just during cold starts to its tough to fake out. I've had a bunch of problems with my SAI the last year....

[Dskvid]

Hi Culi,
How did this story end? I have been clearing this codes for 1 bank only on my C7 and know that Audi wont repair it under warranty unless both banks are coding. So I got to know the end of this story please?

[S4'ed]

It is required for federal emissions, so nobody wants the legal liability to disable it in the ECU coding. If you know what you are doing with the ECU coding, it is probably trivial to remove the SAI diagnostic check.

The SAI diagnostic routine monitors the air pressure before the SAI combi valves. I think there is a way to fake out the diagnostic so that the DTC code is not set even though the air passages in the head are clogged.

[Snowmonkey]

It is required for federal emissions, so nobody wants the legal liability to disable it in the ECU coding. If you know what you are doing with the ECU coding, it is probably trivial to remove the SAI diagnostic check.

The SAI diagnostic routine monitors the air pressure before the SAI combi valves. I think there is a way to fake out the diagnostic so that the DTC code is not set even though the air passages in the head are clogged.

Goddamn i would love that. I've had one bank throwing a code for the past 3 years, but the only one wont throw while i'm still in the extended warranty period.

[repnaudi]

I have to resurrect this as im currently being haunted by this too. My fault comes back too quickly to get my inspection done. Did any of you guys do it yourself? If so do you mind sharing details on exactly what's needed. I've seen the video but they don't go into depth on everything that needs to be removed. I would like to go into this fully confident I have everything I need to complete this successfully.

[thaifoodninja]

I have to resurrect this as im currently being haunted by this too. My fault comes back too quickly to get my inspection done. Did any of you guys do it yourself? If so do you mind sharing details on exactly what's needed. I've seen the video but they don't go into depth on everything that needs to be removed. I would like to go into this fully confident I have everything I need to complete this successfully.

which codes are you getting? I fixed it myself after a bunch of troubleshooting by replacing both combis. Here is another thread you might want to read up on: https://www.audizine.com/forum/showt...1#post13993591

[Mark_Karlsson]

@snowmonkey: I see you've done a lot of research on the secondary air injection problems. I recently cleaned the ports in the cylinder head on a 2009 A6 Quattro 3.0. I saw that Audi sells a pressure washer attachment for $900, so I made my own! I'm interested in trying to sell some of these as they are easy to fabricate, but I'm worried about patent infringement. I called a patent lawyer and he said that I needed to commit to $5K to $10K. I've been attempting to navigate the U.S. patent office but I can't find the patent for the Audi tool (part # VAS6825). The way I made the tool is quite a bit different from the Audi tool but it works well. I wondered if you have any ideas on how I could sell this to Audizine members without getting sued. I could sell this tool for under $200 and still make a good profit. If you have any thoughts, I'd really appreciate hearing them.

Mark

[S4'ed]

I doubt Audi patented the tool. There is nothing financially to be gained (for Audi) by protecting that tool...they are not in the tool selling business, and it is such a super-niche application.
The "magic" of the Audi tool is the right-angle spray tip, and the measurement scale so that it can be inserted the correct depth to spray into each of the 3 individual SAI ports that run to the exhaust ports.

Concerning the AC system, the AC condensor can be swung out of the way, with the flexible rubber hoses still connected, so that the Freon does not need to be released and recharged.

Since I intend to keep my S4 for a very long time, and I expect my SAI ports to eventually clog, I will then spend some time to develop a circuit that taps into the SAI pressure sensor signal, to fool the ECU that the SAI system is not clogged. Unfortunatly I have no motivation to do this until I run into this problem...too many projects on my plate.

If anyone else wants to do this, have at it. Basically, at engine start, the ECU checks the SAI air pressure (as measured by the pressure sensor) at 4 or so different operating conditions of the SAI pump and the two combi valves. If the measured SAI "backpressure" falls within a certain range (unique to each of the 4 operating conditions), then the diagnostic test passes and there is no DTC set. If a port is clogged, or a combi valve does not open/close, or the SAI pump doesn't work, then one or more of the measured backpressure values will not be within the acceptable range (for that operating condition), and the SAI DTC is set. Using a Rasberry Pi micro, one could easily output an analog voltage that replaces the real SAI pressure sensor output signal (0 to 5VDC), that tells the ECU that the SAI backpressure is within the normal range. The Rasberry needs to sense the 12V drive signals to the pump, and the two Combi valve solenoids, to determine which of the 4 diagnostic operating modes the system is in, to then generate the appropriate simulated sensor DC output voltage to the ECU. The first step to developing this is to measure the SAI Pressure sensor signal output level during each of the 4 diagnostic operating modes, on a car that does not have an SAI clog.

See pages 38 thru 41 of the "Audi 3.0 V6 TFSI engine with Roots blower Self-Study Program 925803" for the technical details of the SAI system and the diagnostic self-test.