Sumit Shah

hi guys, I'm going crazy changing part after part and not being able to find a solution.

So I received the engine light and it read secondary air injection solenoid (n112) - open or short circuit.

So far I have changed the SAI pump and checked the hosing which was all fine. The pump is working well, the fuse was changed as well. I've changed the MAF sensor too. I'm lost because I don't know what else to do or check so I decided to post here where the REAL Audi experts are!

Any help is is appreciated and if possible, please include pictures of what I should be looking for.

Steamboat

Did you change the N112 solenoid?

Sumit Shah

Hi, thanks for the reply! I did a little bit of research but I'm not too sure where that is located or how to go about it. I'm not sure where I could even buy that part. If you could point me in the right direction, I'd appreciate t greatly.

Steamboat

The N112 solenoid is located at the center back of the engine, mounted on the right side of the tray that sits under the small engine cover with the 4 ring logo.

I believe the solenoid has one electrical connector and two vacuum line connections. To replace the solenoid, just disconnect these connections from the old solenoid and install them on the new solenoid.

You can certainly get the part at a dealer. I don't know if any online stores carry it.

Steamboat

Also, if you have a volt/ohm meter, it would be wise to verify the solenoid is bad before replacing it. The manual says you should read between 25 and 35 ohms across the solenoid's electrical terminals. If you hook a voltmeter up to the electrical connector terminals you should get a voltage when you start the car. The manual doesn't say what the voltage will be, but I would guess it would be very near your battery voltage.

Sumit Shah

Great info! I really appreciate your response. Would you be able to include a image so I know that I'm looking at the same exact thing as you are.

Steamboat

The N117 solenoid valve is the rectangular device in the right-center of the photo with the white lettering on it.

Sumit Shah

Just to be clear... did you mean n112 solenoid? Or is that the n117? Thanks

Steamboat

I meant N112.

Sumit Shah

Ok so i located the part and I ordered it online (OEM part). Hopefully I'll get it soon and that it solves my problem! I will update here once I receive and install the new N112 solenoid.