The secondary air pump is staying on even when the key is removed from the car. It was cycling on and off when I noticed it about 1hr after I switched the car off and had to unplug it to turn it off. I let the pump cool down and when I plugged it back in it stays on constantly. Any help or suggestions on what may be the problem and how to fix it woul be great.

Also, would it cause any long term problems w/ the car if I drive the car with it unplugged for a while? Thanks in advance.

 

What fault code you get?

 

I don't have a VAGCOM to pull the code fault. I was hoping that someone may have had a similar problem to give me suggetions on what to look for.

 

I have the same problem. It didn't throw a code until I unplugged it and left it unplugged after it killed my battery one night. I have yet to figure out what is causing it, most of the feedback I got a few months ago from other users on here when I posted about it back then told me I could have one of three things: a bad relay, bad wiring, or bad pump. 7 months later, it's still unplugged cuz I have no clue where to start troubleshooting and certainly don't want to feed the stealership a couple hundred bucks to trace the problem. Wish I could be more help. If you find any useful info, hit me up, cuz I need it too haha

 

A4CRAGMAN, I called my Audi shop and they said it may be what you suggested and I'm going to take a look at the car this weekend and I'll let you know if I can trace the problem.

 

A4CRAGMAN. I was finally able to work on the car tonight and it was the Secondary Air Injection relay located in the ECU/relay box under the hood right in front of the driver side wiper. The relay was sticking and all it took was unplugging it and pluging it back in to reset the relay. It's a cheap grey plastic "Made in Portugal" relay and I will probably replace it w/ a good old Bosch relay. I figure replacing the relay would be cheaper in the long run than having to replace a burned out SAP if the relay ever stuck again. I'll take pics tomorrow and will try to post them for you on where and which relay to replace.

 

Fantastic! Thanks man, just the info I've been looking for. The pics will be much appreciated, especially if you have a different year than I and the relay is in a slightly different location. I know all the relays are in that same general area, but I'm fairly certain mine are under the driver's side dash, not under the hood so pictures will definitely be useful.

 

A4Cragman,
Most of the relays are in the passenger compartment but there are a few under the hood. From what I've researched and heard, only the mid year 2000 and newer Audi's w/ Tiptronic have the SAP installed in them. The relay is the grey relay w/ the "373" marked on top of it. I included a pic of the engine compartment and of the relay/ECU box so you know where it's located.

To remove the relay/ECU cover you have to remove both the wiper arms and plastic cowling that partially covers the box to get to all the screws. My relay was stuck in a closed position and just unplugging the relay and plugging it back in worked for me but you may want to, or have to, replace yours if it's been a long time because your's may be frozen closed by now.

Don't quote me and hold me liable on this but the relay looks like it's a standard 30A SPST blade type relay w/ possibly either a built in diode or resistor to prevent voltage kickback. I'm going to pick up a Bosch one to replace the what seems like a cheap cost reduction "Made in Portugal" unit. I use to use the Bosch SPDT all the time with very few if any issues. Hope this solves your problem and please give me an update if this worked for you too.

 

Oh yeah, I was able to clear the "Check Engine" code by disconnecting the battery for a few minutes. Just be sure you have your radio code before you do this.

 

Thanks for the pics, I at least have a better idea of what to look for now. I had my ecu box open when I installed my LED auxiliary lights a few weeks back and that definitely wasn't in there, in fact my whole box is square, no little offshoot where that relay is sitting on yours so hopefully it's chillin under the dash with all the other relays I saw while installing those auxiliary lights and I don't have to chase after it too much.

Even though mine is a 98, I know I have the pump because I've seen it, and the CEL code I've been reading the last 7 months tells me I have insufficient secondary air injection (P0422 if I remember right) and that code didn't pop up til I unplugged that pump when it kept coming on even when the car was off so I know I have it, now the fun part is going to be tracing where that actual relay is. I would assume it would be the same gray 373 relay as yours so that's what I'll start looking for when I get a chance to look haha

Thanks again for the pics and info, couldn't have posted at a better time, I got emissions testing coming up and have to have this figured out by then, hopefully this'll take care of it. I'll let you know if it does.