I was under the hood the other day and i noticed that the fiber braided vac lines on top of my throttle body (2.8) are cracked up and falling apart. Is this bad for the engine? Does it rob power in anyway? The lines arent falling off but i can tell that if i muscle them they will crack for sure.

Replace? Silicon tubes?

 

I've noticed that on my oldcar. The factory lines are verygood quality and even if the outer braiding in wasted, the lines are probably fine. i had a 1996 2.8 a4 and i replaced all the lines i could hoping to solve a problem and it did not. This was at 198,000 miles. all the lines wereholding up. Unless you arehaving problems or codes i would just leave it. But Preventive maintenance on an Audi great practice, especially things you can do your self.

 

the braided cover will hold in moisture and crack the lines. If you can, replace them and use silicone since it wont crack like rubber.

 

^^^ exactly, i found out i had a boost leak because the fabric was covering some big cracks in the inner hose and i couldn't see them

 

Well cincy i have seen 3.0 A4's with all that vac line replaced with silicon tube after a supercharger install so it looks under the hood. I liked the way it looked very much.

So bad vac lines can rob the 1.8T of power (boost)...can it do the same for a 2.8?

 

Any holes in a vac line are bad for the car. Just get some rubber lines from your local parts store, their cheap and easy to replace. Silicone won't get you anything but a look, and it's really expensive.

 

Uh, not really. The vacuum lines on a 2.8 just below the cover are the first thing I used to check on oil changes. I kept a roll of replacement line in my toolbox and replaced the visible ones as a courtesy simply because they were so commonly torn, especially if the car had over 60K miles. The braiding was often the only thing holding them together and looking at them would cause them to disintegrate to nothing.

And yes, they do need to be there. IIRC, they are for the tuning flaps in the intake manifold on a 2.8.

 

Any body got a link for some new line? maby i can pick up some from a shop or something...that would be alot easier. Im thinkin blue...

 

bump

 

does anyone have a link to some replacement silicone vac lines like anmagro was asking about?