Ok. Long story short, I don't know where this goes or what it is. Could someone please fill me in? I think its missing a connector. Any help would be greatly appreciated!



Let me know if you guys need better pictures.

 

Pics don't work.
Even if I cut&paste the links, Photobucket says "Page not found."


-Ted

 

Really? Comes up when I open this window? Let me upload them again. Sorry about that Ted.

 

Here are some more pictures.

Maybe I can find where it goes on the UIM and it will look familiar by placement? Gotta try something..

Thanks for all the help so far guys. I appreciate it!

 

WTF???

It has nothing to do with boost...
It will not cause the turbo to make more boost when removed...

It's just for idle control, and I think it's for power steering.

Basically, it's for idle control, and you can throw it away and cap the vacuum fittings.


-Ted

 

Looks like the bypass air control valve, or BAC. It adjusts the idle to compensate for additional load from the AC and power steering.

 

Looks like this is where it will mount to on the UIM. Someone please correct me if I'm mistaken.

My real question now I guess is, does this have anything to do with emissions? Judging by Ted's reply probably not, but I live in California and just want to make sure I have everything for smog.

 

nope, it's the Air Bypass Solenoid Valve on S4 or the Accellerated Warm Up solenoid on S5 turbos.

And to the OP It goes where you had it on the manifold.

The N/A have em too but it's on the back of the manifolds.

I am pretty sure.

 

I appologize if I confused anyone. I don't know why I didn't post earlier, but its an S4 T2

 

Actually, I was wrong, its not the BAC. Thee BAC is larger than that.

 

Just in case you didn't realize it, NJGREENBUD wroter the real skinney on what the heck it is. Pay attention to NJ.

And he's right. The non turbo series four has the same outfit (AIR BYPASS SOLENOID VALVE) but it's on the left rear side of the engine just aft of the BAC's location. That one has an additional relay involved with it. Its relay is located near the front right side of the engine bay and engages for seventeen seconds duing a cold start to drive the starting rpms up to close to 3000rpm for .....seventeen seconds. The Turbo cars do not have the additional relay but still preform the same way. For seventeen seconds.

It's written in the FSM.

 

+1 NJ and Hailers post.

Not sure if some of the other posters are jokers or just spreading BS/misinformation. Look for a pipe nipple and two threaded holes nearby for that bracket/valve to mount on. Not sure where it goes in the TII, so I won't comment on that.

Unlike the BAC valve (which varies the amount it is open depending on the electrical pulse to it from the computer based on engine electrical load at idle), the Air bypass valve is either on or off, depending on the state of the air bypass relay, controlled by the computer.

You can read this up in the FSM, linked in my sig.

 

I deleted all the wrong and ridiculous posts. If you don't know, don't guess and therefore don't post.

The part is the air bypass solenoid valve. Called the ABS valve, or more commonly ASV valve.

It opens during cold starts to allow more air into the engine for the 3K startup as HAILERS already posted. It also helps keep the engine idle from dropping when the power steering is turned to extremes.

All this information (and more!) is found in the Factory Service Manual (see FAQ for free download) and the Haynes manual.

 

Reading the FSM, I just want to get my interpretation straight. Like Ted suggested, I should be able to remove it and cap the fittings on the BAC, correct?

 

I found the thread rather amusing at first.

 

Why would you want to do this?

If you do not have power steering, then you can eliminate the ASV. Otherwise keep it in place.

Do not remove the BAC. It's how the ECU controls your idle.

 

Ah, thanks! I've been looking at the left side under the BACV where this little guy is just dangling loose. Hopefully I will figure out where is goes and secure it now.

 

I don't have power steering. And I wasn't removing the BAC. I just wanted to make sure it was ok to cap off the nipple that the ASV connects to on the BAC?

 

OMG.. This thread made me LOL..

 

AH, now I've got it. The reason I'm having so much trouble figuring out where this goes is because there is an additional bracket for it on S4 N/A's. I am missing the bracket marked with a red X below:

 

I always wire mine up to a switch, it will bump up your idle by 1-1.5k.. Great for autocrossing when you need to keep the revs up..

 

GAH!!

I went out and bought that bracket from the junk yard. I even took the time to clean it up and paint it black...



And the PITA part of it is... I have no mounting points on the dynamic chamber!



What am I missing here people?