Secondary Air Injection System issues - RESOLVED
#1
Secondary Air Injection System issues - RESOLVED
My 2006 XJ8 4.2L is giving DTC P0411 Code. If I drive the car immediately after start up all is well. If I start up and let it idle for 30 seconds before driving it produces a P0411 code.
I have been studying the Workshop Manual and it appears it could be a number of components in the Secondary Air Injection System. The Air Pump for example might be the problem, but that entails removing the front bumper just to get at it.
If anyone has experienced this failure, I would be interested in knowing what they found and how they diagnosed the problem.
The car drives fine no problems, but it is coming up for an emissions test and I believe it will fail because of the MIL light.
Any suggestions would be appreciated.
I have been studying the Workshop Manual and it appears it could be a number of components in the Secondary Air Injection System. The Air Pump for example might be the problem, but that entails removing the front bumper just to get at it.
If anyone has experienced this failure, I would be interested in knowing what they found and how they diagnosed the problem.
The car drives fine no problems, but it is coming up for an emissions test and I believe it will fail because of the MIL light.
Any suggestions would be appreciated.
#2
#3
Secondary Air Flow Problems
I found the 'Vacumm Control Valve' was not closing properly allowing the vacumm to escape and hence the vacumm reservoir was never filled.
(This vacumm is used to operate a switching valve to allow secondary to pass to the exhaust system)
The inlet manifold has a small plastic hose coming off which feeds a small plastic valve (black and white in color). I removed this valve and applied vacumm from a mitty vac pump and observed the leak down, within seconds the vacumm had gone.
Sprayed WD40 into both sides of the valve and shook the valve, some dirt and carbon came out. Retested the valve and it now holds the vacumm good for more than 5 minutes. Problem solved.
(This vacumm is used to operate a switching valve to allow secondary to pass to the exhaust system)
The inlet manifold has a small plastic hose coming off which feeds a small plastic valve (black and white in color). I removed this valve and applied vacumm from a mitty vac pump and observed the leak down, within seconds the vacumm had gone.
Sprayed WD40 into both sides of the valve and shook the valve, some dirt and carbon came out. Retested the valve and it now holds the vacumm good for more than 5 minutes. Problem solved.
#5
Secondary Air Injection issues
Yes you need to remove the main engine cover. There are four cross head screws holding the cover down. Turn each screw about 1/4 of a turn to loosen. You will need to remove the oil filler cap. Then just remove the cover.
Replace the oil filler cap to prevent dirt from entering.
Follow the air intake until you reach the aluminum section. Attached to the aluminum part, pointing towards the rear of the engine, is a small rubber piece, which has two very small vacumm hoses coming off (approx 1/8" dia.). One of those hoses leads to the vacumm control valve (about 6" away). It is about the size of a quarter and black and white in color. Carefully remove the valve for testing.
Operation as I understand it, is the manifold vacumm passes through this one-way valve and the vacumm is stored in a reservour located in the right hand side fender. This vacumm is then available to operate a vacumm switching valve, when it receives a signal from the ECU. Operation of the valve allows the Secondary Air to flow to the exhaust.
This fixed my problem, but are you sure your Secondary Air Pump is running and providing air? You can hear the Air Pump running on initial start-up; it is located behind the front bumper right hand side. It only runs for about 60 seconds after initial cold start up. Hope this helps!
Replace the oil filler cap to prevent dirt from entering.
Follow the air intake until you reach the aluminum section. Attached to the aluminum part, pointing towards the rear of the engine, is a small rubber piece, which has two very small vacumm hoses coming off (approx 1/8" dia.). One of those hoses leads to the vacumm control valve (about 6" away). It is about the size of a quarter and black and white in color. Carefully remove the valve for testing.
Operation as I understand it, is the manifold vacumm passes through this one-way valve and the vacumm is stored in a reservour located in the right hand side fender. This vacumm is then available to operate a vacumm switching valve, when it receives a signal from the ECU. Operation of the valve allows the Secondary Air to flow to the exhaust.
This fixed my problem, but are you sure your Secondary Air Pump is running and providing air? You can hear the Air Pump running on initial start-up; it is located behind the front bumper right hand side. It only runs for about 60 seconds after initial cold start up. Hope this helps!
#6
Thank you for your detailed instructions. I took the engine cover off and followed the little 1/8 " diameter hard vacuum hose to the black and white vacuum control valve and discovered that the vacuum hose was broken leaving the T junction just past the control valve. It was actually broken twice - once in each 'direction' leading to the T. I rejoined them with thin strips of duct tape, started the car for the first time today (it is only 15 C. here in Halifax) and the P0411 code which I cleared again last night didn't come back on. I will order the replacement vacuum hose kit C2Z4729 for a more permanent solution.
The following users liked this post:
Uncle Av (10-30-2023)
#8
I just ordered C2C22716 $28 USA and decided to also order the 6 inch rubber vacuum line that goes from the AIR solenoid to the diverter valve. That vacuum hose is less then $3 USA and the part # is xr849100. I'm dealing with P0414 and mistakenly ordered the diverter valve C2C32933 only to find out that my diverter valve was OK. I'm waiting on the AIR vacuum switching solenoid xr855179 $19 USA.
This is for my 2006 NA x350
This is for my 2006 NA x350
#9
Secondary Air Injection System error code P0411
XJ 8 L 2006 - Appreciate reading these posts but have received the same error code P0411 and have been for about a month at cold start a high winding sound which was this pump. No longer as of today hearing the noise but the error code light also came on today. Does anyone have the process for changing this or where to go to review this process? Thank you.
#10
my experience with P0411 and secondary air injection
Here are four of the several components that make up the secondary air injection system that I replaced to fix P0411 / P0414 DTC's.
The switching solenoid and diverter valve are located on a mounting bracket at the front of the engine
and blocked from access by the top radiator hose on my 2006 NA x350. For scale, the photo was taken
on 12 inch tile. The pics do NOT include the blower motor, the blower motor relay nor the hose
that connects the blower to the diverter valve. The hose that connects the blower output clamps to the
diverter valve input looks like a heater hose and snakes around up from the blower and traverses half
way across the engine and looks just like the auxillary heater hose ( same diameter and runs parallel to it ).
The diverter valve flared end attaches to a downward stainless tubing that T's to the right and left feeding
the exhaust manifolds. From what I can tell, there is no check valve in the diverter. Instead, the forced air from
the blower is enough to overcome any exhaust back pressure. Of course when vacuum drops at the diverter via
the switching solenoid, the heavy diaphragm closes and prevents exhaust gases from reaching the blower which always
coincides with blower cycling off. The plastic switching solenoid has in interesting fitment using a interference clip
sharing the same mounting bracket as the diverter valve which bolts to said bracket.
You'll see a closeup side angle view of the solenoid to show the retaining clip or detent. If you remove
the solenoid you have to be careful not to mangle the clip and be careful not to chew up the alignment
ridge under the clip. The alignment ridge fit's into a tight fitting slot in the mounting bracket
and so don't twist the solenoid to free it from the bracket. Otherwise, if you have to reattach it,
you'll have to fashion a figure 8 loop of safety wire or heat resistant lacing around the diverter valve and around
the solenoid to keep it secured to the mounting bracket. This holds true when mounting a new solenoid too...
be careful and study the mounting bracket by locating the slot for the alignment ridge and cut-away for the
interference clip/detent.
I replaced all the components in the pic - which may not have been necessary - but am glad that I did.
It all started with just the diverter valve and realized that I needed to replace the switching solenoid instead.
The old diverter valve bench tested OK. Oh Well. After nearly ten years of exhaust gases pummeling the rubber
diaphram in the diverter valve, I'm OK with having a new one now. When diagnosing the P0411 / P0414 issue there was
air hissing when monkeying with the vacuum line connector at the switching solenoid. So I decided to replace both vacuum
lines as they are reasonably priced.
After replacing these 4 components, the P0414 would surface after each each cold start along with CEL. If wasn't until I replaced
front distribution box 5 Amp fuse xx with a good one that my P0414 went away.
One theory is the switching solenoid was going bad and perhaps picking only partially to the open position
resulting in inadequate air flow through the diverter valve causing P0411, until which point 5Amp threshold exceeded and pop goes Fuse xx.
When fiddling with the old parts for the photo setup I decided to bench test the long narrow vacuum line to
make sure for example the integral check valve was OK etc. What I learned is the vacuum fitting that connected to the
reservoir coupler at the top of the right shock tower was completed clogged with some taupe colored crud.
And so now I'm beginning to formulate Theory two - which I believe is the real reason for the P0411 and that it was actually caused by lack of reserve vacuum at cold start.
This would prevent the diverter valve from opening until there was enough continuous vacuum at the throttle body.
Imagine the engineering and cost containment negotiations that went into the decision to include the miniature vacuum reservoir and where to put it!
If it wasn't necessary, then it would not have been added. The Secondary or rather the - Oh by the way - Air Injection system
is nothing short of a Rube Goldberg. Point being, that without the reserve vacuum at cold start, the ECM will post
P0411 instead of first checking for example is the engine is running at 500 rpm ( which would produce enough vacuum to the switching solenoid to
operate the diverter valve). I suspect the downstream O2 sensors are used along with some imperfect algorithm to determine if enough
fresh air is making it to the exhaust manifolds from the moment the ignition cycles on. That's why sometimes P0411 shows up on occasion
and most people just clear the trouble code don't care.
However, if the P0411 occurs frequently enough, then you will care if your state or municipality administers strict emission enforcement.
This is because the Secondary Air System Monitor takes about 300 miles of combined city Highway driver to turn that monitor off.
There is a specific drive cycle that can be exercised to meet criteria for satisfying the Secondary Air System Monitor completion state but
I didn't feel like trying it.
So if you get the P0411 once a week and then clear the code, there is a good chance you'll have trouble at emission testing even
though no CEL is illuminated.
Oh and one other interesting tidbit relative the Secondary Air System Monitor and Evaporative System Monitor and Oxygen Sensor Heater Monitor
and that is that all three of those monitors cycle to "Not Complete" if you disconnect and reconnect the battery like I did after installing a new AGM
Group 49 battery. And even without the CEL illuminated, emission or smog test will NOT pass with "n" number of those three monitors
posting an incomplete status. It requires a drive cycle or maybe more to cycle those to complete. The AutoEnginuity OBDII scanner or any other high end scanner will
reveal whether the secondary air injection system is complete.
Bob
PS. Only 16 months after replacing all the parts described above including the hin vacuum line with integral check valve, I started getting Secondary Air Injection related codes again. Turns out the vacuum line -
part number - C2C22716 Hose-Vacuum - got brittle and cracked and began leaking. So had to order a replacement and haven't had an issue now for 12 months...
The switching solenoid and diverter valve are located on a mounting bracket at the front of the engine
and blocked from access by the top radiator hose on my 2006 NA x350. For scale, the photo was taken
on 12 inch tile. The pics do NOT include the blower motor, the blower motor relay nor the hose
that connects the blower to the diverter valve. The hose that connects the blower output clamps to the
diverter valve input looks like a heater hose and snakes around up from the blower and traverses half
way across the engine and looks just like the auxillary heater hose ( same diameter and runs parallel to it ).
The diverter valve flared end attaches to a downward stainless tubing that T's to the right and left feeding
the exhaust manifolds. From what I can tell, there is no check valve in the diverter. Instead, the forced air from
the blower is enough to overcome any exhaust back pressure. Of course when vacuum drops at the diverter via
the switching solenoid, the heavy diaphragm closes and prevents exhaust gases from reaching the blower which always
coincides with blower cycling off. The plastic switching solenoid has in interesting fitment using a interference clip
sharing the same mounting bracket as the diverter valve which bolts to said bracket.
You'll see a closeup side angle view of the solenoid to show the retaining clip or detent. If you remove
the solenoid you have to be careful not to mangle the clip and be careful not to chew up the alignment
ridge under the clip. The alignment ridge fit's into a tight fitting slot in the mounting bracket
and so don't twist the solenoid to free it from the bracket. Otherwise, if you have to reattach it,
you'll have to fashion a figure 8 loop of safety wire or heat resistant lacing around the diverter valve and around
the solenoid to keep it secured to the mounting bracket. This holds true when mounting a new solenoid too...
be careful and study the mounting bracket by locating the slot for the alignment ridge and cut-away for the
interference clip/detent.
I replaced all the components in the pic - which may not have been necessary - but am glad that I did.
It all started with just the diverter valve and realized that I needed to replace the switching solenoid instead.
The old diverter valve bench tested OK. Oh Well. After nearly ten years of exhaust gases pummeling the rubber
diaphram in the diverter valve, I'm OK with having a new one now. When diagnosing the P0411 / P0414 issue there was
air hissing when monkeying with the vacuum line connector at the switching solenoid. So I decided to replace both vacuum
lines as they are reasonably priced.
After replacing these 4 components, the P0414 would surface after each each cold start along with CEL. If wasn't until I replaced
front distribution box 5 Amp fuse xx with a good one that my P0414 went away.
One theory is the switching solenoid was going bad and perhaps picking only partially to the open position
resulting in inadequate air flow through the diverter valve causing P0411, until which point 5Amp threshold exceeded and pop goes Fuse xx.
When fiddling with the old parts for the photo setup I decided to bench test the long narrow vacuum line to
make sure for example the integral check valve was OK etc. What I learned is the vacuum fitting that connected to the
reservoir coupler at the top of the right shock tower was completed clogged with some taupe colored crud.
And so now I'm beginning to formulate Theory two - which I believe is the real reason for the P0411 and that it was actually caused by lack of reserve vacuum at cold start.
This would prevent the diverter valve from opening until there was enough continuous vacuum at the throttle body.
Imagine the engineering and cost containment negotiations that went into the decision to include the miniature vacuum reservoir and where to put it!
If it wasn't necessary, then it would not have been added. The Secondary or rather the - Oh by the way - Air Injection system
is nothing short of a Rube Goldberg. Point being, that without the reserve vacuum at cold start, the ECM will post
P0411 instead of first checking for example is the engine is running at 500 rpm ( which would produce enough vacuum to the switching solenoid to
operate the diverter valve). I suspect the downstream O2 sensors are used along with some imperfect algorithm to determine if enough
fresh air is making it to the exhaust manifolds from the moment the ignition cycles on. That's why sometimes P0411 shows up on occasion
and most people just clear the trouble code don't care.
However, if the P0411 occurs frequently enough, then you will care if your state or municipality administers strict emission enforcement.
This is because the Secondary Air System Monitor takes about 300 miles of combined city Highway driver to turn that monitor off.
There is a specific drive cycle that can be exercised to meet criteria for satisfying the Secondary Air System Monitor completion state but
I didn't feel like trying it.
So if you get the P0411 once a week and then clear the code, there is a good chance you'll have trouble at emission testing even
though no CEL is illuminated.
Oh and one other interesting tidbit relative the Secondary Air System Monitor and Evaporative System Monitor and Oxygen Sensor Heater Monitor
and that is that all three of those monitors cycle to "Not Complete" if you disconnect and reconnect the battery like I did after installing a new AGM
Group 49 battery. And even without the CEL illuminated, emission or smog test will NOT pass with "n" number of those three monitors
posting an incomplete status. It requires a drive cycle or maybe more to cycle those to complete. The AutoEnginuity OBDII scanner or any other high end scanner will
reveal whether the secondary air injection system is complete.
Bob
PS. Only 16 months after replacing all the parts described above including the hin vacuum line with integral check valve, I started getting Secondary Air Injection related codes again. Turns out the vacuum line -
part number - C2C22716 Hose-Vacuum - got brittle and cracked and began leaking. So had to order a replacement and haven't had an issue now for 12 months...
Last edited by locorebob; 10-11-2017 at 09:40 AM. Reason: additional info
The following 4 users liked this post by locorebob:
#11
One more consideration when diagnosing issues related to this subject is don't blast the thin vacuum line with compressed air... you could damage the integral check valve. You can however rent a hand vacuum pump ( Mighty Vac ) at your local auto parts chain store and pull off the vacuum line on top of the right shock tower. Apply just a few pounds 1 or 2 lbs of vacuum to make sure the check valve closes and holds vacuum. Then test the reservoir by applying vacuum maybe 5 lbs to that coupling on the right shock tower. FWIW, the reservoir is hidden between fender liner under the right fender with a short line to the coupler on top of the right shock tower. Once you know the Integral Check Valve is OK and the reservoir holds vacuum, now move to the throttle body connection. You may or may not need to remove the vacuum line at the switching solenoid to plug that end of the T. I don't know if that valve is normally closed. If it is, then leave it attached because it's hard to get to. After pulling the vacuum line from the throttle body, apply 5 lbs and see if it holds vacuum. Do all this WITHOUT the engine running and WITHOUT ignition on. This is considered a static bench test.
Last edited by locorebob; 10-12-2017 at 12:24 PM. Reason: typo - wordo
#12
Diagram/photo?
Hey, everyone. Sorry to dig up a dead post, but I had an oil change done and it threw the same code, so I pulled off the engine cover and there lay the broken pieces of plastic vacuum line. The guy probably leaned on the cover hard enough to destroy the brittle plastic. Bygones.
My issue is that I have a rubber boot on the intake with two broken hoses. You've solved that the top one goes to the black and white check valve, where does the other go? The C2C22716 diagram only shows 1 hose originating from the intake. Can someone snap a photo of their routing so that I could sort this out?
My issue is that I have a rubber boot on the intake with two broken hoses. You've solved that the top one goes to the black and white check valve, where does the other go? The C2C22716 diagram only shows 1 hose originating from the intake. Can someone snap a photo of their routing so that I could sort this out?
#15
Can you please send me photos
Yes you need to remove the main engine cover. There are four cross head screws holding the cover down. Turn each screw about 1/4 of a turn to loosen. You will need to remove the oil filler cap. Then just remove the cover.
Replace the oil filler cap to prevent dirt from entering.
Follow the air intake until you reach the aluminum section. Attached to the aluminum part, pointing towards the rear of the engine, is a small rubber piece, which has two very small vacumm hoses coming off (approx 1/8" dia.). One of those hoses leads to the vacumm control valve (about 6" away). It is about the size of a quarter and black and white in color. Carefully remove the valve for testing.
Operation as I understand it, is the manifold vacumm passes through this one-way valve and the vacumm is stored in a reservour located in the right hand side fender. This vacumm is then available to operate a vacumm switching valve, when it receives a signal from the ECU. Operation of the valve allows the Secondary Air to flow to the exhaust.
This fixed my problem, but are you sure your Secondary Air Pump is running and providing air? You can hear the Air Pump running on initial start-up; it is located behind the front bumper right hand side. It only runs for about 60 seconds after initial cold start up. Hope this helps!
Replace the oil filler cap to prevent dirt from entering.
Follow the air intake until you reach the aluminum section. Attached to the aluminum part, pointing towards the rear of the engine, is a small rubber piece, which has two very small vacumm hoses coming off (approx 1/8" dia.). One of those hoses leads to the vacumm control valve (about 6" away). It is about the size of a quarter and black and white in color. Carefully remove the valve for testing.
Operation as I understand it, is the manifold vacumm passes through this one-way valve and the vacumm is stored in a reservour located in the right hand side fender. This vacumm is then available to operate a vacumm switching valve, when it receives a signal from the ECU. Operation of the valve allows the Secondary Air to flow to the exhaust.
This fixed my problem, but are you sure your Secondary Air Pump is running and providing air? You can hear the Air Pump running on initial start-up; it is located behind the front bumper right hand side. It only runs for about 60 seconds after initial cold start up. Hope this helps!
#17
All,
Thanks so much for the info! It's helped a lot as I try to tackle P0414.
Question: I hooked a vaccuum guage after the check valve, and when the car turns off, should it go to 0? Does it hold vaccuum after the car is not running?
So far I checked the blower, blower relay, visually inspected connections. The check valve leaks by slightly when I apply a small pressure, but I'm not sure if that leak by is normal. This test was a crude one, I just put a hose on the valve and blew air the wrong way gently, and noticed the majority of the air did not flow, only a very small amount did.
Thanks so much for the info! It's helped a lot as I try to tackle P0414.
Question: I hooked a vaccuum guage after the check valve, and when the car turns off, should it go to 0? Does it hold vaccuum after the car is not running?
So far I checked the blower, blower relay, visually inspected connections. The check valve leaks by slightly when I apply a small pressure, but I'm not sure if that leak by is normal. This test was a crude one, I just put a hose on the valve and blew air the wrong way gently, and noticed the majority of the air did not flow, only a very small amount did.
#18
All,
Thanks so much for the info! It's helped a lot as I try to tackle P0414.
Question: I hooked a vaccuum guage after the check valve, and when the car turns off, should it go to 0? Does it hold vaccuum after the car is not running?
So far I checked the blower, blower relay, visually inspected connections. The check valve leaks by slightly when I apply a small pressure, but I'm not sure if that leak by is normal. This test was a crude one, I just put a hose on the valve and blew air the wrong way gently, and noticed the majority of the air did not flow, only a very small amount did.
Thanks so much for the info! It's helped a lot as I try to tackle P0414.
Question: I hooked a vaccuum guage after the check valve, and when the car turns off, should it go to 0? Does it hold vaccuum after the car is not running?
So far I checked the blower, blower relay, visually inspected connections. The check valve leaks by slightly when I apply a small pressure, but I'm not sure if that leak by is normal. This test was a crude one, I just put a hose on the valve and blew air the wrong way gently, and noticed the majority of the air did not flow, only a very small amount did.
#19
Johnmsullivan, Did you ever get this figured out? I have a 2010 XF and I had the P0411 code. I had (non-dealer) shop replace the replace secondary air pump/diverter valve assembly/solenoid valve. Now I'm experiencing the same thing you are/did. Loud fan noise at start but after about 10seconds it goes away. I have an ODB-II reader. Have cleared the code a few times but it comes back every time.
#20
Thank you for this. I had replaced a secondary air pump that was not working, but kept getting a P0411 code. I was in the process of locating the cable mentioned in this thread to find out that my whole wiring of this part was brittle and had completely broke off. Waiting now for the replacement part, but thanks for sharing this info as I was really confused why my new pump wasn't resolving the problem since it did need replacing.