Secondary air injection fault - help please!

[nick4501]

Hi guys.

After replacing the water temp sensor and cleaning out my throttle body, I'm now left with just one error message in VAGCOM - Secondary air injection system incorrect flow detected.

After reading several posts on here, I'm lead to believe that it's likely due to a leaking vacume hose, but I don't know where to start looking. Can someone point it out on a picture for me please?

Thanks!

 

[Andrew@A.L.D]

I have this problem and removed the lot

I found that the plastic pipe leads to the air box was split and the was water in the pump

 

[nick4501]

Interesting. Is it still unfixed? I've googled the hell out of this problem, but am yet to come across a decent picture-based solution for the average newbie...

 

[Andrew@A.L.D]

Same as a Audi

How to repair

http://uk-mkivs.net/forums/p/141240/940861.aspx#940861

Removing it altogether you have to bung a few things up and wire in a resister

 

[mark_sarah]

I had this problem. Removed mine problem now gone. Easy and cheap to do, it took me 40 minutes. search 'SAI' you will find several guides.

 

[nick4501]

I've come across those SAI removal posts, but would rather try to plug the leak than rip the whole thing out. Can someone provide a photo of the a3 engine bay, circling the pipes that I should be looking at for leaks?

Will this error cause performance loss? I'm debating a remap, but I'm guessing I would need to resolve this problem before-hand...?

 

[nick4501]

Anyone...?

 

[Welly]

The 'incorrect flow detected' error can mean several things.

1: Your N112 valve (underneath the black plate by the dipstick assembly) is broken and/or not working properly. Most common.

2: Your SAI pump is cream crackered.

3: You have an air leak in the system (least likely as would have to be a colossal air leak.)

I wouldn't worry too much personally. Firstly, the SAI pump is pointless. Mine is removed and has been for a long while.

I have just left the plug cable tied to something in the engine bay - I didn't bother with the resistors or any of that malarky.

I occasionally get a SAI pump fault code - which I ignore.

It has no effect of the running of the car, will not change performance in any way, so it gets cleared.

First, check the nipples on your N112 valve aren't snapped or broken in some way, then check the pipe which goes from the N249 assembly to the N112 valve, and also the pipe from the N112 valve to the combi valve on the side of the head.

 

[nick4501]

Thanks Welly - that is EXACTLY what I needed to know.

One thing that concerns me is your mention of an air leak... I posted about excessive bubbles in my reservoir (http://www.audi-sport.net/vb/showthread.php?99138) - would this imply that I do actually have such a leak?!

Thanks!

 

[nick4501]

Also - what do I do if the valve itself is shafted?...How do I go about getting a replacement?...Is it an Audi only job?

 

[Andrew@A.L.D]

Ditch the lot, not needed

make up a blanking plug for the head and air box and thats it

 

[nick4501]

I hear that suggestion a lot, but I really don't have the balls to go ripped wires out and inserting resisters, etc!

I'm going to have a good look around the engine bay for leaks...but my main concern is Welly saying that it's possibly due to a large air leak in the system...this just seems too coincidental when coupled with the millions of air bubbles coming to the top of my reservoir!