Engine light came on the other day. Stopped by my indy shop to pull the codes and it turns out a couple vacuum lines were disconnected. I wasn't all that surprised as I just got the car back on Monday from the body shop (someone backed into me about 2 months ago) and we all know how they forget to hook things back up.

Due to the condition of the stock Audi vacuum lines my mechanic replaced them with new silicone lines. $3 in parts, $17 in labor. No biggie considering so many other times he has looked at my car quickly, pulled codes, diagnosed issues at no cost.

Just thought some of you may want to take a look at your vacuum lines if you have '02ish models as 1 of the 2 lines replaced was pretty tattered and dirty.

We also noticed that the airflow intake valve's plastic arm on the low side is broken. Something about an $800 repair kit, but my mech said he'll see if they offer only the replacement arm.

 

Everyone should replace their vacuum lines if they are anywhere near the 90k mark.

Show a pic of the "intake valve's plastic arm" thing, i don't know what you are talking about.

 

I can get a picture up tomorrow, but I found out what the proper technical terms for the area of topic. The change-over-valve? Also known as the cam adjusters? The little plastic arm piece on the mechanical side of the diaphragm. If this makes sense and you know a better way to "patch" it for the time being please let me know.

Again, I can take a picture tomorrow if that doesn't help.

 

The cam adjuster is under the valve cover, is that what your talking about like in your other thread? Or something else?

 

Here is a diagram of the area in question. This isn't exactly to scale as the plastic arm connected to the diaphragm is a little longer than shown.

 

That's for a variable length intake runner system. Does the 4.2 have that? Option 1 is to disconnect both vacuum motors (just diconnect and block the vacuum lines) and see if you can tell the difference. You will probably wind up with the intake in the short runner position and lose a little torque off the line. Top end should be unaffected.

For $800 you should be able to get a custom machined part with gold plating! Or, try some of the new plastic glues with a bit of reinforcment and you should be able to repair the current arm.

Bob

 

Oh yeah man your fucked, i had one of those come into my shop. The 4.2L intake manifold is like a 3.0L, basically it has mechanical servos built into the manifold to achieve short and long runners for maximum horsepower and torque between all RPM's. I had to replace the entire manifold because they didn't sell the arms seperately.

 

Would it be safe to use some aluminum to brace the broken arm? (like a real broken arm) Or is the weight of the plastice piece important? I can't see that it would be.

 

The weight isn't important, just that it has enough ridigity to open the flaps. You can try using some fast drying JB WELD, but i don't know how much force it can hold.

 

Sorry to wake up this old thread but this was a recently discussed topic in our shop and I figured I'd just comment here instead of starting a new topic...

(Re: part#N0203535 - vacuum hose - [id]3.5mm [od]7mm)
As many of you already know, the common, cloth-braided, VWaG vacuum hose certainly has a "lifespan"(...to put it politely). I do agree that upgrading to a high quality silicone hose is a good idea...but please choose your silicone hose carefully. While the OE "crapuum" hose has its well known flaws, it also has a spec'd amount of wall strength to resist collapsing under vacuum...some cheap, low-durometer(ie:soft) silicone hoses do not and will throw cels, drive you batty, ect.. High density silicone is the key...if you can easily squish the silicone tubing between your thumb and forefinger, it's too soft.

UberTeile