Secondary Air Injection System Fault P0492

I have a 2005 545i and am getting a P0492 fault. I believe that the pipe is cracked that goes from the secondary injection pump to the valve on either side of the back of the engine. P0492 would lead me to believe the problem is on the drivers side. I can hear the pump come on when the engine is first started and believe that I can hear air leaking from the pipe. Has anyone replaced this pipe and is it possible to do it without removing the intake manifold. It is very tight where the pipes connect to the valves. If the intake needs to be removed, what gaskets will I need and what else should I consider replacing while I am at it.

Thanks in advance for any advise.

I have this code as of this morning. Just starting the research. Has anyone solved?

I reset the code and it ran clear for a couple of days. It came back this morning (P0492) secondary air bank.

However, is this a true fault? The secondary air only runs for a couple of minutes. My code appears at least 15 minutes into driving. The air pump is not even running at this point. Is this a false positive. Could it actually be a faulty O2 sensor?

On my Z3 had simialr problem and SES came on with in first minute of cold start. This was a bad hose.

I just don't think it is an air leak when the pump isn't even running.

Did you guys figure out what was causing this on your cars? I have a 05 545i with 120k and I just got the error message after it sat for a month except my code is (P0491) which is the left bank.

This car is like a HOT Physco girl friend!! I love it and I can't stand it at the same time!!
It has other issues also. I should probably open this in a new thread but since your here.
Have either of you had smoke come from your tail pipe when you first take off after you sit at a light for more than a minute idling?

Thanks for listening!

yes, I have an 05 545i sport with 140k and this has happened to me several times after sitting at a long light or just sitting with the engine running for a few minutes. Anyone have any suggestions it is greatly appreciate. I have had the P0491 & 0492 code for a month now. Still working on how to figure out exactly what the problem is; the pump, the valve, the hose ??? Thanks for any input.

I had that code on my car one of two secondary smog pumps went bad and the long thin air hoses that cary the secondary air cracked in places thus losing secondary air and sounding a code. It looks like the valve can also lose its seal around its base at exaust header. Get the code diagnosed, then DIY the valves and air hoses.

Hey Guys,
I too have this issue for about 2 weeks. Reset the code twice using my new Android Torgue app (Droid Razr) in conjunction w/new Bluetooth OBDII (Excel) diagnostic plug device. Code came back again...now after some research I have to dive in and do a complete systematic air flow check. This links may help:


https://wiki.bentleypublishers.com/d...es+2004+-+2005



I will check back in w/ my findings!


Thanks to everyone for the posts in this forum, I have learned a lot and saved thousands!

Steve

Originally Posted by svett

Hey Guys,
I too have this issue for about 2 weeks. Reset the code twice using my new Android Torgue app (Droid Razr) in conjunction w/new Bluetooth OBDII (Excel) diagnostic plug device. Code came back again...now after some research I have to dive in and do a complete systematic air flow check. These links will help: 2nd one is pg 6

http://www.bimmerfest.com/forums/sho...ary+air+system

https://www.bavauto.com/newsletter/2...newsletter.pdf

https://wiki.bentleypublishers.com/d...es+2004+-+2005

I will check back in w/ my findings!


Thanks to everyone for the posts in this forum, I have learned a lot and saved thousands!

Steve

The first two links are not applicable to your 545i. Unlike the 6 cylinder engines, the N62 SA system does not use vacuum operated check valves, and the fresh air is routed through the heads into the exhaust ports, not into the headers. The CEL is activated when the O2 sensors don't sense a lean shift due to fresh air entering the exhaust during SAP operation. This can be due to a cracked y-pipe under the intake manifold, stuck check valves, or clogged SA ports in the heads. Unfortunately, clogged ports are quite often the problem. This requires removal of the heads and drilling out the carbon. Some people over in the E65 forum have claimed success in opening up the ports using solvents and wire brushes, but I spent a week doing that with no success. So, it's head removal time for me. Fortunately, I have the means and the know-how to do the job myself.

Originally Posted by Stephen Max

The first two links are not applicable to your 545i. Unlike the 6 cylinder engines, the N62 SA system does not use vacuum operated check valves, and the fresh air is routed through the heads into the exhaust ports, not into the headers. The CEL is activated when the O2 sensors don't sense a lean shift due to fresh air entering the exhaust during SAP operation. This can be due to a cracked y-pipe under the intake manifold, stuck check valves, or clogged SA ports in the heads. Unfortunately, clogged ports are quite often the problem. This requires removal of the heads and drilling out the carbon. Some people over in the E65 forum have claimed success in opening up the ports using solvents and wire brushes, but I spent a week doing that with no success. So, it's head removal time for me. Fortunately, I have the means and the know-how to do the job myself.

I saw the YouTube having the video to show how to clear the clogged passage.

by pouring sea foam , or solvants into the ports...Wont that damage the catalitic converters?? from carbon breaking up and clogging the converters ???

Hello,

Seafoam has been a reputation over 50 years and it is natural base oil.
It has been proved that it won't harm any catalic converter at all.

You can research online to see how seafoam has been safe for catalic converter.
Ric

Originally Posted by Ricardo567

Hello,

Seafoam has been a reputation over 50 years and it is natural base oil.
It has been proved that it won't harm any catalic converter at all.

You can research online to see how seafoam has been safe for catalic converter.
Ric

I see,,,, ok does sea foam actually desolve carbon, or does the carbon flake off,

What about broken up carbon particles clogging up the air passages in the converter,,, wonder if it would b a good idea to remove the converters while performing that task,, avoiding ur cats clogging up with carbon debris ,, ,

The white smoke coming out is the dissolved carbon burning off, not the Seafoam. In the new or low mileage engine, you won't see that much white smoke. Sea Foam actually helps to clean the catalytic elements, restoring its efficiency, and reducing the "rotten egg" odor you occasionally smell from some catalytic converters.
I have tried this task as video showing and never have had catalytic converter failure so far. I don't think you need to disconnect the catalytic converter at all. So many people in the world using Seafoam now. Yyu can search on YouTube for "Seafoam" and will see a lot of videos for this seafoam smoke.

Originally Posted by Ricardo567

The white smoke coming out is the dissolved carbon burning off, not the Seafoam. In the new or low mileage engine, you won't see that much white smoke. Sea Foam actually helps to clean the catalytic elements, restoring its efficiency, and reducing the "rotten egg" odor you occasionally smell from some catalytic converters.
I have tried this task as video showing and never have had catalytic converter failure so far. I don't think you need to disconnect the catalytic converter at all. So many people in the world using Seafoam now. Yyu can search on YouTube for "Seafoam" and will see a lot of videos for this seafoam smoke.

well at 90,000 mi. I was thinking bout doen this on my 545.. as a routine, preventive mantanece to avoid clogged passages.. Wonder how long it takesfor the passages to start clogging up...and how often seafoam should b applied,,,, to maintain the passages clean...

Hello HF,

Depend on how the car being driven, BMW is designed to perform as almost as race car, It will automatic unclog the passage if we drive aggressive as BMW intended to perform. However, we've like to take care our car and drive at moderate speed, long idle, and stop and go; it will be clogged around 70,000 miles.
To extend the mileage of between cloggings, BMW cars need to drive at 5,000 RPM (highway at 3rd gear up to 60 mph) for 10 minutes once a week; more than 10 minutes probably will over heat the transmission and won't be recommended. Or the other way around is to follow the Youtube procedure above twice a year or 7,000 miles whichever comes first.

Ric

thx fo rthe info Ricardo,,,, will have to get on it real soon,, dont wana take the heads off to unclogg the passages. if it can be avoided....

The reason why these passages get clogged is due to leaking exhaust valve stem seals. The oil leaks down the back of the valve and eventually becomes carbonized due to the heat. The secondary air holes are right next to the exhaust valve guides. I've done this job many times (I'm a BMW tech)

[QUOTE=bmwoem1;7340307]The reason why these passages get clogged is due to leaking exhaust valve stem seals. The oil leaks down the back of the valve and eventually becomes carbonized due to the heat. The secondary air holes are right next to the exhaust valve guides. I've done this job many times (I'm a BMW tech)[/QUOTE I was wondering how the passages get clogged , Okay,,,,,,,so is the valve steam seal failure due to the 15,000 mi oil change intervals that bmw recomends....And also is the higher oil temperature on the 545 the reason for gasket and the seals leaking prematurely due to the higher temps breaking the oils protection ?? Due to bmw not equipting the 545 with an oil cooler ??

This issue is also common on the 550, 650, and 750... and they have oil coolers, so I wouldn't blame it on that. I've seen them leak as low as 45k miles.... it depends how hard you drive the car and extended idling periods.

Originally Posted by bmwoem1

This issue is also common on the 550, 650, and 750... and they have oil coolers, so I wouldn't blame it on that. I've seen them leak as low as 45k miles.... it depends how hard you drive the car and extended idling periods.

Then prolonged and constant high rpms is the reason for valve stem seal failure ?... So 15.000 mi oil change vescosity loss and higer oil temps hold no blame for premature seal and gasket leaks like on 545,s... isnt that why bmw went back to equipting oil coolers on the 550??

I don't think driving at high speed to maintain high RPM won't make the valve stem seal failure premature. BMW is designed from Europe and they can run no speed limit at Autobalns, as the fourth longest highway system in the world (7,982 mi). When driving at 120 mile/hr the rpm will boot up to 5,000 roughly.
To me, extended idling periods, driving in the city (stop and go frequently), oil changing interval, and brand of oil contribute to the valve stem seal failure premature.

wonder if it could just be a bad stem seal design ....

Well I am not sure on his hydroloc theory I think he is just lucky. There can be at least one exhaust valve open when the engine is off. The sea foam "liquid" could potentially enter the cylinder through this open valve, which means some sea foam could remain under the compression stroke. This would be bad I would think.

I tried a couple weeks ago to use the Sea Foam spray, not the liquid. The Sea foam spray is intended to be used for many things but specially the air intake. The can comes with about a 1 foot red spray tube.

Thinking I had a sticky exhaust valve I sprayed up inside the "Y" pipe on my 545i. I took a 1/8 ( maybe smaller) drill bit and drilled a hole in the top of the LH pipe as I have a P0492 only( about 2 inches past the "Y"). The hole was just big enough to put about 6 inches of the red spray tube into. I then started the car when cold. In this cold temp the pump runs a good 60 to 90 seconds. While the SAS pump was running I sprayed for about 4 seconds into the pipe. I then quickly shut the car off and let sit overnight. The next day I was ready to go. When I started the car indeed a cloud of white smoke came out. I drove for a couple blocks and the smoke dissipated. This was not carbon though this is sea foam as it is an oil - smokes when hot duh. (Video stated smoke was from carbon).

At least the smoke tells me I have some open passage but not enough to allow the volume of air from the SAS.

I have now done this a total of 3 times with no luck. No other problems have occurred as a result of doing.

To the point of the video I am indeed trying to see if a safe cleaner will dissolve the carbon over time. I don't think it will. I have heard and read that the carbon is very hard and must be removed while the head is off.

I have decided to give up on this SES light and P0492 code. I have 11 months to go for the next emissions test. Its only for initial start and causes zero drive-ability problems. To think anyone would spend 6 to 10K ( 1 or 2 heads) does not make sense. When I am ready to drop that kind of coin, it will be a down payment on my next one.

Originally Posted by georgeflint

I have a 2005 545i and am getting a P0492 fault. I believe that the pipe is cracked that goes from the secondary injection pump to the valve on either side of the back of the engine. P0492 would lead me to believe the problem is on the drivers side. I can hear the pump come on when the engine is first started and believe that I can hear air leaking from the pipe. Has anyone replaced this pipe and is it possible to do it without removing the intake manifold. It is very tight where the pipes connect to the valves. If the intake needs to be removed, what gaskets will I need and what else should I consider replacing while I am at it.

Thanks in advance for any advise.

I did this on my 528. I imagine the repair is similar. The pump on mine is behind the inner lining of the front passenger side wheel. After removing the cover the pump is easily accessible. I bought a section of comparable diameter hose that was flexibile enough to route and made the connections between the pump and the metal tube it attaches to next to the exhaust manifold. Problem solved.

Hogie,

The hydroloc theory, to me it is right. Look at the exhaust cycle. If Seafoam being entered when one of exhaust valve opens, then the Seafoam will be pushed out since during the exhaust cycle, the piston is moving up and the valve opens all the time. Only during other cycles, which is the exhaust valve being closed, but not complete seal, Seafoam can get through and stay in the cylinders to be compressed when all vavles are closed. That's why he said we should limit the amount of Seafoam, roughly 1 oz at a time for each treatment. He also said the 6 or 8 cylinders engines rest on about 15 degrees to the left or right so when the all exhaust valves were closed (Seafoam unable to get through quickly like an opened exhaust valve cycle), the Seafoam will penetrate on the top of them and gradually drift down to the sides of the exhaust ports.

In soaking, I had been tried one can without soaking, it would not work until I started to soak overnight or 2 days then drove at third gear for 10 minutes up to 5,000 RPM on the highway, and finally I unclogged the blockages. I didn't know for sure whether I did use up to 2 cans or just soaked and drove hardly that contributes to unclog passage.

In spraying, the amount of Seafoam you put in the passage won't be enough to dissolve the carbon built up. Remember carbon built up in the passage head is tough like a coal because the tremendous heat makes it hard. To break it, we have to be patient and repeat the process until it fixes. Some of members here used Seafoam to pour in the tube, reconnect the tube, started engine for couple minutes then rested it for 20 minutes, and ran on highway; they didn't soak it overnight. They have reported that they unclogged it after using up to 2 cans of Seafoam.

Good luck.