Secondary Air Valve Replacement - How to access?

[magus4286]

Having found this post before attempting to remove/delete the secondary air valves myself and at least gaining from it the confidence that it was possible to do from the top without the crazy official BMW procedure -- and after a lot of frustration finally succeeding (!) with the right set of tools -- I thought I'd leave some guidance here on how I did it for future forum searchers. I'm no pro, but was able to pull it off.

Creating space to work:

0. I'll note that I still had the engine-side heat shields and sound deadening panels still in place, which really cuts into your working space, especially on the drivers side.

1. Obviously you need to remove the cowl, as others said. I already needed to remove the other cowl pieces underneath (that seal over the windshield) for other reasons, which further required removing the strut tower braces. Pretty sure that will be required to have the working room for your hands

2. As I was deleting the entire secondary air system, I first removed the pump itself and hoses, which means first removing the plenum. You may be able to avoid that and just need to disconnect the hoses from the valves and get them out of the way.

3. Regarding the drivers side in particular, I should also note that I had just completed a full HVAC delete, so having the coolant hoses and A/C lines out of the way probably helped. Disconnecting the coolant lines temporarily may give you some working space. I also pulled the aux water pump off the body to pull the coolant lines forward and tie them out of the way.

A word about clearance and tool selection:

The primary challenge, once you've given yourself enough room to get your hands in the working space, is identifying what I'll call the "Goldilocks" tools for the job. The biggest challenge I found was having a ratchet/socket combination where the socket was long enough to clear the valve body and reach the bottom nut while still being short enough to get it into position in front of the firewall. On the drivers side, I found it even mattered how wide the ratchet head was for getting it into position between the nut and the firewall. They are 10mm hex nuts, FYI. The top nut is easy enough to remove, as are the bolts attaching the valves to the heat shields. For the latter, a flex-head ratchet is your friend.

Passenger side valve:

Starting with the easy side, where there is quite a bit more room to work. I was able to reach the bottom nut using a 1/4" drive deep socket without too much difficulty. FWIW, I used a GearWrench 120XP (flex head) ratchet, which has a ~6.75" handle. That handle length worked pretty well here, I thought.

Once I got the nut most of the way off, I finished removing it carefully by hand to not drop it into the abyss below....

Driver side valve:

This sucked. As alluded to above, the key to removing the bottom nut was finding a socket just long enough to clear the valve while fitting in the tiny working space in front of the fire wall. Working with 1/4" drive b/c space is so limited, deep sockets are too long (hit heat shield on firewall) and standard length are too short to reach around the valve body.

I purchased this kit: GEARWRENCH 10 Pc. 1/4" & 3/8" Drive 6 Pt. Single Size Socket Set, 10mm - 80319, to have some options. Available on Amazon. It has a "mid-length" 10mm socket that you can see is a little longer than a standard length. I also has a flex socket (which becomes a rigid or wobble socket with a few wraps of painters tape...) that is a little longer than that, but shorter than the deep socket. This gave me a pretty good set of lengths to work with. I bought the kit rather than the individual sockets since the magnetic might also have come in handy for this job. Plus. I'm sure I'll lose a few 10mm along the way and have some more spares now...

Combined with my 120XP 1/4" ratchet, the mid-length was actually a little short and the taped-stiff flex head socket was the right length -- but the ratchet head was too big to get into position behind the valve! That led to this guy:

GEARWRENCH 1/4" Drive 72 Tooth Quick Release Locking Flex Slim Head Ratchet, 12" - 81030

The slimmer head was the big benefit here. It's actually just as thick as the 120XP head, but significantly more narrow, which made it possible to get into position. The long handle also helped. Because of the design, the socket is actually pushed out a little bit farther from the ratchet head and the mid-length 10mm socket was now just the right length combined with this ratchet. The trick to getting it into position was starting with the head/socket in the transmission tunnel and bringing it in behind the valve, with the socket parallel to the firewall (this is why you needed the slim head), pointing in the direction you're moving toward the nut, and above the shield underneath to get in behind the valve and then rotate it into place over the nut. You're basically sliding it in through the narrow gap between the valve and the firewall.

After loosening with the ratchet, similar to the passenger side, I finished removing it by hand. Unfortunately, it fell.... I had placed some paper shop towels underneath to catch it just in case, but only behind and not over the shield underneath, which it rolled down into the abyss.... Turns out it landed on top of the metal reinforcement plate. I fished around for a while with magnetic grab tools through the opening for the oil drain, through the wheel wells, and from behind after removing the transmission splash shield, before giving up and just removing the reinforcement plate thinking it was caught elsewhere -- but found it resting on the plate as I lowered it.

--

I ultimately installed the BMW Motorsport GT4 valve block-off plates (with fresh gaskets -- pulling off the old gaskets is underrated annoying, FYI) in place of the valves, which is a cinch. Installing a new valve would require the more painful reverse of the above.

Hope this saves someone some pain/frustration!

Here's the winning ratchet / socket combo, in all its glory:

[killakill]

Originally Posted by magus4286

Having found this post before attempting to remove/delete the secondary air valves myself and at least gaining from it the confidence that it was possible to do from the top without the crazy official BMW procedure -- and after a lot of frustration finally succeeding (!) with the right set of tools -- I thought I'd leave some guidance here on how I did it for future forum searchers. I'm no pro, but was able to pull it off.

Creating space to work:

0. I'll note that I still had the engine-side heat shields and sound deadening panels still in place, which really cuts into your working space, especially on the drivers side.

1. Obviously you need to remove the cowl, as others said. I already needed to remove the other cowl pieces underneath (that seal over the windshield) for other reasons, which further required removing the strut tower braces. Pretty sure that will be required to have the working room for your hands

2. As I was deleting the entire secondary air system, I first removed the pump itself and hoses, which means first removing the plenum. You may be able to avoid that and just need to disconnect the hoses from the valves and get them out of the way.

3. Regarding the drivers side in particular, I should also note that I had just completed a full HVAC delete, so having the coolant hoses and A/C lines out of the way probably helped. Disconnecting the coolant lines temporarily may give you some working space. I also pulled the aux water pump off the body to pull the coolant lines forward and tie them out of the way.

A word about clearance and tool selection:

The primary challenge, once you've given yourself enough room to get your hands in the working space, is identifying what I'll call the "Goldilocks" tools for the job. The biggest challenge I found was having a ratchet/socket combination where the socket was long enough to clear the valve body and reach the bottom nut while still being short enough to get it into position in front of the firewall. On the drivers side, I found it even mattered how wide the ratchet head was for getting it into position between the nut and the firewall. They are 10mm hex nuts, FYI. The top nut is easy enough to remove, as are the bolts attaching the valves to the heat shields. For the latter, a flex-head ratchet is your friend.

Passenger side valve:

Starting with the easy side, where there is quite a bit more room to work. I was able to reach the bottom nut using a 1/4" drive deep socket without too much difficulty. FWIW, I used a GearWrench 120XP (flex head) ratchet, which has a ~6.75" handle. That handle length worked pretty well here, I thought.

Once I got the nut most of the way off, I finished removing it carefully by hand to not drop it into the abyss below....

Driver side valve:

This sucked. As alluded to above, the key to removing the bottom nut was finding a socket just long enough to clear the valve while fitting in the tiny working space in front of the fire wall. Working with 1/4" drive b/c space is so limited, deep sockets are too long (hit heat shield on firewall) and standard length are too short to reach around the valve body.

I purchased this kit: GEARWRENCH 10 Pc. 1/4" & 3/8" Drive 6 Pt. Single Size Socket Set, 10mm - 80319, to have some options. Available on Amazon. It has a "mid-length" 10mm socket that you can see is a little longer than a standard length. I also has a flex socket (which becomes a rigid or wobble socket with a few wraps of painters tape...) that is a little longer than that, but shorter than the deep socket. This gave me a pretty good set of lengths to work with. I bought the kit rather than the individual sockets since the magnetic might also have come in handy for this job. Plus. I'm sure I'll lose a few 10mm along the way and have some more spares now...

Combined with my 120XP 1/4" ratchet, the mid-length was actually a little short and the taped-stiff flex head socket was the right length -- but the ratchet head was too big to get into position behind the valve! That led to this guy:

GEARWRENCH 1/4" Drive 72 Tooth Quick Release Locking Flex Slim Head Ratchet, 12" - 81030

The slimmer head was the big benefit here. It's actually just as thick as the 120XP head, but significantly more narrow, which made it possible to get into position. The long handle also helped. Because of the design, the socket is actually pushed out a little bit farther from the ratchet head and the mid-length 10mm socket was now just the right length combined with this ratchet. The trick to getting it into position was starting with the head/socket in the transmission tunnel and bringing it in behind the valve, with the socket parallel to the firewall (this is why you needed the slim head), pointing in the direction you're moving toward the nut, and above the shield underneath to get in behind the valve and then rotate it into place over the nut. You're basically sliding it in through the narrow gap between the valve and the firewall.

After loosening with the ratchet, similar to the passenger side, I finished removing it by hand. Unfortunately, it fell.... I had placed some paper shop towels underneath to catch it just in case, but only behind and not over the shield underneath, which it rolled down into the abyss.... Turns out it landed on top of the metal reinforcement plate. I fished around for a while with magnetic grab tools through the opening for the oil drain, through the wheel wells, and from behind after removing the transmission splash shield, before giving up and just removing the reinforcement plate thinking it was caught elsewhere -- but found it resting on the plate as I lowered it.

--

I ultimately installed the BMW Motorsport GT4 valve block-off plates (with fresh gaskets -- pulling off the old gaskets is underrated annoying, FYI) in place of the valves, which is a cinch. Installing a new valve would require the more painful reverse of the above.

Hope this saves someone some pain/frustration!

Here's the winning ratchet / socket combo, in all its glory:
Attachment 2538452

Thank you so much, this will help me alot. Thanks!

[patroklai]

Originally Posted by magus4286

Having found this post before attempting to remove/delete the secondary air valves myself and at least gaining from it the confidence that it was possible to do from the top without the crazy official BMW procedure -- and after a lot of frustration finally succeeding (!) with the right set of tools -- I thought I'd leave some guidance here on how I did it for future forum searchers. I'm no pro, but was able to pull it off.

Creating space to work:

0. I'll note that I still had the engine-side heat shields and sound deadening panels still in place, which really cuts into your working space, especially on the drivers side.

1. Obviously you need to remove the cowl, as others said. I already needed to remove the other cowl pieces underneath (that seal over the windshield) for other reasons, which further required removing the strut tower braces. Pretty sure that will be required to have the working room for your hands

2. As I was deleting the entire secondary air system, I first removed the pump itself and hoses, which means first removing the plenum. You may be able to avoid that and just need to disconnect the hoses from the valves and get them out of the way.

3. Regarding the drivers side in particular, I should also note that I had just completed a full HVAC delete, so having the coolant hoses and A/C lines out of the way probably helped. Disconnecting the coolant lines temporarily may give you some working space. I also pulled the aux water pump off the body to pull the coolant lines forward and tie them out of the way.

A word about clearance and tool selection:

The primary challenge, once you've given yourself enough room to get your hands in the working space, is identifying what I'll call the "Goldilocks" tools for the job. The biggest challenge I found was having a ratchet/socket combination where the socket was long enough to clear the valve body and reach the bottom nut while still being short enough to get it into position in front of the firewall. On the drivers side, I found it even mattered how wide the ratchet head was for getting it into position between the nut and the firewall. They are 10mm hex nuts, FYI. The top nut is easy enough to remove, as are the bolts attaching the valves to the heat shields. For the latter, a flex-head ratchet is your friend.

Passenger side valve:

Starting with the easy side, where there is quite a bit more room to work. I was able to reach the bottom nut using a 1/4" drive deep socket without too much difficulty. FWIW, I used a GearWrench 120XP (flex head) ratchet, which has a ~6.75" handle. That handle length worked pretty well here, I thought.

Once I got the nut most of the way off, I finished removing it carefully by hand to not drop it into the abyss below....

Driver side valve:

This sucked. As alluded to above, the key to removing the bottom nut was finding a socket just long enough to clear the valve while fitting in the tiny working space in front of the fire wall. Working with 1/4" drive b/c space is so limited, deep sockets are too long (hit heat shield on firewall) and standard length are too short to reach around the valve body.

I purchased this kit: GEARWRENCH 10 Pc. 1/4" & 3/8" Drive 6 Pt. Single Size Socket Set, 10mm - 80319, to have some options. Available on Amazon. It has a "mid-length" 10mm socket that you can see is a little longer than a standard length. I also has a flex socket (which becomes a rigid or wobble socket with a few wraps of painters tape...) that is a little longer than that, but shorter than the deep socket. This gave me a pretty good set of lengths to work with. I bought the kit rather than the individual sockets since the magnetic might also have come in handy for this job. Plus. I'm sure I'll lose a few 10mm along the way and have some more spares now...

Combined with my 120XP 1/4" ratchet, the mid-length was actually a little short and the taped-stiff flex head socket was the right length -- but the ratchet head was too big to get into position behind the valve! That led to this guy:

GEARWRENCH 1/4" Drive 72 Tooth Quick Release Locking Flex Slim Head Ratchet, 12" - 81030

The slimmer head was the big benefit here. It's actually just as thick as the 120XP head, but significantly more narrow, which made it possible to get into position. The long handle also helped. Because of the design, the socket is actually pushed out a little bit farther from the ratchet head and the mid-length 10mm socket was now just the right length combined with this ratchet. The trick to getting it into position was starting with the head/socket in the transmission tunnel and bringing it in behind the valve, with the socket parallel to the firewall (this is why you needed the slim head), pointing in the direction you're moving toward the nut, and above the shield underneath to get in behind the valve and then rotate it into place over the nut. You're basically sliding it in through the narrow gap between the valve and the firewall.

After loosening with the ratchet, similar to the passenger side, I finished removing it by hand. Unfortunately, it fell.... I had placed some paper shop towels underneath to catch it just in case, but only behind and not over the shield underneath, which it rolled down into the abyss.... Turns out it landed on top of the metal reinforcement plate. I fished around for a while with magnetic grab tools through the opening for the oil drain, through the wheel wells, and from behind after removing the transmission splash shield, before giving up and just removing the reinforcement plate thinking it was caught elsewhere -- but found it resting on the plate as I lowered it.

--

I ultimately installed the BMW Motorsport GT4 valve block-off plates (with fresh gaskets -- pulling off the old gaskets is underrated annoying, FYI) in place of the valves, which is a cinch. Installing a new valve would require the more painful reverse of the above.

Hope this saves someone some pain/frustration!

Here's the winning ratchet / socket combo, in all its glory:
Attachment 2538452

So wait, are you deleting the valves? What are you using in place?

[magus4286]

Originally Posted by patroklai

So wait, are you deleting the valves? What are you using in place?

As it said at the very end of the post:

"I ultimately installed the BMW Motorsport GT4 valve block-off plates (with fresh gaskets -- pulling off the old gaskets is underrated annoying, FYI) in place of the valves, which is a cinch."

The GT4 unsurprisingly doesn't have a secondary air system, so it comes with those installed. Also a factory part cap replaces the tube to the intake elbow.

[patroklai]

Originally Posted by magus4286

As it said at the very end of the post:

"I ultimately installed the BMW Motorsport GT4 valve block-off plates (with fresh gaskets -- pulling off the old gaskets is underrated annoying, FYI) in place of the valves, which is a cinch."

The GT4 unsurprisingly doesn't have a secondary air system, so it comes with those installed. Also a factory part cap replaces the tube to the intake elbow.

Yep, I knew about the GT4, just didn't think the parts could be purchased by anyone other than a GT4 owner. Haven't touched on this topic in a few years tho so I may be outdated.

How are you coding it off? With tune software or is there an option in NCS expert?

[magus4286]

Motorsport catalog parts can be purchased from one of the BMW Motorsport dealers. In my case I knew someone who worked at one who knew I was installing it in an unregistered (i.e. offroad only) car, which as I understand it is the important part.

Re: coding, it can only be taken care of with a DME software tune (Epic in my case).

[patroklai]

Originally Posted by magus4286

Motorsport catalog parts can be purchased from one of the BMW Motorsport dealers. In my case I knew someone who worked at one who knew I was installing it in an unregistered (i.e. offroad only) car, which as I understand it is the important part.

Re: coding, it can only be taken care of with a DME software tune (Epic in my case).

I have mine coded off currently, but that may change when I go S/C. Was hoping there was a better solution other than asking the vendor to code them off.

Thanks, this is very helpful.

[killakill]

Changed mine today and this is how it looked after 337000km. Just had to change the passenger side. It wasn't too bad I did remove the whole wiring harness and moved it out of the way to get space which helped alot. The inside of mine was clogged so I cleaned it out before putting the new one in.

[patroklai]

I would bet that's what mine look like. 😂

[bmwlover0725]

I've done this job from the top of the engine bay. It's an absolute BITCH to do without moving the motor or anything out of the way. You'll want to play around with the right tool combo to get the bolts off/on, but it is doable. I did this along with stuffing a wire brush through each side to clean out carbon... as Mike said, you're better off with a tune. I'm glad I fixed it because I'm obsessive like that, but what a PITA and waste of time.

[Scrippy]

Just did both banks and it is a fucking nightmare! I had to make two tools due to lack of space. I could see why the dealer just drops the powertrain for this actually. Lol I'm proud of my little tool here, gonna make a freggin necklace out of it! It was for the lower jerkoff bolt on the drivers side valve!

[patroklai]

Rofl!! Nice bro. Love the creativity.

[MidnightM3]

Got 27B1 and 2743 and am thinking this is the culprit. Can anyone familiar with this issue verify that these codes point to a Bank 2 issue of the SAV?

[MidnightM3]

Originally Posted by MidnightM3

Got 27B1 and 2743 and am thinking this is the culprit. Can anyone familiar with this issue verify that these codes point to a Bank 2 issue of the SAV?

Ran an initial bottle of Cataclean through the system and the CES is gone and hasn’t returned. Ran a second bottle through the end of the next tank of gas for good measure.

Was hoping it would clean up the carbon buildup on the Secondary Air System Valves, seems to have worked.

[limitedslipnick]

Originally Posted by MidnightM3

Ran an initial bottle of Cataclean through the system and the CES is gone and hasn’t returned. Ran a second bottle through the end of the next tank of gas for good measure.

Was hoping it would clean up the carbon buildup on the Secondary Air System Valves, seems to have worked.

Do you still have your primary cats? I am running a primary cat delete with an alpine tune. The SES light has just come on with the secondary air valve replacement code coming up. I’m in the process of trying to get it coded out, but am interested in the results you have had with your car.

[MidnightM3]

Originally Posted by limitedslipnick

Do you still have your primary cats? I am running a primary cat delete with an alpine tune. The SES light has just come on with the secondary air valve replacement code coming up. I’m in the process of trying to get it coded out, but am interested in the results you have had with your car.

No, I have test pipes, a supercharger and tune. Before you code it out, maybe consider running a $26-29 bottle of Cataclean through it. Follow the instructions, when that bottle/process is complete run another and repeat. CES hasn’t returned since I did this. It’s worth the attempt. I plan to do a bottle every 3-6 months given the results I had.

[bmwdonut]

Originally Posted by MidnightM3

Ran an initial bottle of Cataclean through the system and the CES is gone and hasn’t returned. Ran a second bottle through the end of the next tank of gas for good measure.

Was hoping it would clean up the carbon buildup on the Secondary Air System Valves, seems to have worked.

How many miles were on your M3 when you ran Cataclean through the system? I'm going down the rabbit hole and I might be running into the same issue. I have 152k miles on my M3.

[Helmsman]

Originally Posted by Scrippy

Just did both banks and it is a fucking nightmare! I had to make two tools due to lack of space. I could see why the dealer just drops the powertrain for this actually. Lol I'm proud of my little tool here, gonna make a freggin necklace out of it! It was for the lower jerkoff bolt on the drivers side valve!

Hahaha........., sometimes one just slip into an old post to find a good laught - thanks mate! Yep, that tool is well worth hanging with your other jewelry...

Ps. I hope my valves never get clogged, damm that look challenging.

[Scrippy]

Originally Posted by Helmsman

Hahaha........., sometimes one just slip into an old post to find a good laught - thanks mate! Yep, that tool is well worth hanging with your other jewelry...

Ps. I hope my valves never get clogged, damm that look challenging.

So I did have to go back in there! I have a post with pics. My problem was the port runner in the head. I used a scope with valves off to look. Passenger side was mega blocked. So I took my hand crafted tool out of the jewelry box for another suckfest. Had to run a gun barrel cleaner through the runner and a few cans of Seafoam. But now I shouldn’t have to go there again!🤞🏻

[Redd]

Anyone know how many mm is the inner diameter of the air hose? Need to find a bung for it.

[Helmsman]

Originally Posted by Scrippy

So I did have to go back in there! I have a post with pics. My problem was the port runner in the head. I used a scope with valves off to look. Passenger side was mega blocked. So I took my hand crafted tool out of the jewelry box for another suckfest. Had to run a gun barrel cleaner through the runner and a few cans of Seafoam. But now I shouldn’t have to go there again!🤞🏻

It doesn't seem to be a very common issue, in fact never heard about it over here (although small community of around 450 E9xMs in Sweden). What is assumingly the main reason for the clogg up, bad fuel?

[Scrippy]

Originally Posted by Helmsman

It doesn't seem to be a very common issue, in fact never heard about it over here (although small community of around 450 E9xMs in Sweden). What is assumingly the main reason for the clogg up, bad fuel?

It’s just an air system that uses filtered air so I am not sure how any debris could get in there. The clogged material in mine was like 2 inches deep from the valves. The other side was fine. It looked more like melted plastic than carbon. My valves, Y-hose and pump were fine the whole time. I’ve only used the highest quality gas California has (91 octane). I can’t understand where the buildup came from. I have seen others complain about this on this forum and M3cutters forum but it’s not really common. I cleared mine around 250,000 miles and 27B0 began being consistent around 230,000. Maybe someone who works on these knows more?