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CEL On for Secondary Air Injection

1K views 8 replies 6 participants last post by  ylwagon 
#1 ·
So I have had the P0411 code on my VW passat for probably a few months. About 6 months ago it came on, was on for a week, then left. Then a few months ago it came on... and did not leave. I tried resetting it just recently using the battery disconnect and discharge, but it returned after about 100 miles. :(

So yesterday I finally decided to diagnose it. First, I turned the car on and off and listened for the pump. I heard what sounded like the pump to me turn on and off. Great! Pulled the plastic shrouding and air ram out over the air filter box, and noticed the connection port on the side of air box closest to the front of the car was a bit loose. Pulled that off, and the gasket/rubber boot was ripped. Got under the car, found the smog pump and pulled on the hoses while the women held the one I disconnected from the air box in her hand. Sure enough, its the connection from the smog pump. Heres a picture with it disconnected and holding the ripped rubber boot
Auto part Wheel Hand Automotive wheel system Finger


My question is, where can I buy this little guy? Do I need to buy a whole new hose? I can go to the junkyard if I must, but I would like fresh rubber for the best seal. Anybody know of a part number or name for this?

Side note: I didn't check for any leaks with the car actually running, so I don't know if this is actually the culprit, or if there is a leak in the hose somewhere else. But just the way the hose was barely held on screamed a lack of air tight to me and figured was the easiest first step to take.
 
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#5 ·
What makes you say that?

For the secondary air pump (SAIP) the miles are irrelevant. It only runs when the car is started with a cold engine and the CEL will come on after (?) number of starts with the O2 sensor not reading the correct values. So count the starts with a cold engine and if you get over 10 or so you are probably good to go.

It should run for about 90 seconds when you start the car cold. One common fault is the relay in the ECU box. Another is the piping as you have found. For the gasket, I'd try a junkyard. It's not a critical seal and VW rubber seems to last pretty well.
Looks like ill be making a trip to the junkyard. I don't think the relay is faulty since I heard (at least I thought) the pump turning on and off.
 
#4 ·
For the secondary air pump (SAIP) the miles are irrelevant. It only runs when the car is started with a cold engine and the CEL will come on after (?) number of starts with the O2 sensor not reading the correct values. So count the starts with a cold engine and if you get over 10 or so you are probably good to go.

It should run for about 90 seconds when you start the car cold. One common fault is the relay in the ECU box. Another is the piping as you have found. For the gasket, I'd try a junkyard. It's not a critical seal and VW rubber seems to last pretty well.
 
#6 ·
That rubber o-ring / flat seal is on the intake air supply, basically it sucks cleaned air from the clean side of air filter housing . The absence of a great seal (such as yours) is not going to prompt a CEL because the ECM is looking for flow of pressurized air from the SAIP and Kombi valve working together. Your damaged o-ring / flat seal could be totally missing and all it would cause is some sucking noise as the SAIP is cycling - the issue of it taking in dirty air is not much to worry about because that dirty air is only going into the exhaust stream - it doesn't enter the engine for combustion air.
 
#8 ·
Thank you for explaining. So only a leak on the output side of the pump or combi valve could cause a CEL? (Besides the obvious pump or valve failure)

On a side note, when I started the car to listen for the pump. I could barely hear it when the car was on, if at all. But when I turned it off, it sounded like a quiet vacuum winding down. I watched a couple videos, and thought theirs all sounded louder. Am I potentially hearing something else?
 
#9 ·
The ECU is expecting a response for excess Oxygen from the sensor, as Iowegian says. If the pump runs, but the sensor doesn't respond, then the air may not be getting into the exhaust as intended. The "combi" valve might be stuck, or not being made to open by the control circuit.
 
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