[Vwdiesel] Quietening Intake System

[Doyt W. Echelberger]

At 11:59 PM 8/13/2005, you wrote:
>Hey All-
>
>......snip...................
>Anyway, the car is much quieter.
>
>However, I'd like it to be quieter still.
>
>I'm wondering if there are any strategies to quiet
>down the intake rattle.
>..............snip................................
>
>David Cook
 >>>>>>>>>>>>>>>>>>>>>>>>>>
My 85 Jetta TD has always made a very annoying loud noise that mostly goes 
away when I test run it without the pleated disposable air filter in place.

Because the rattle is almost gone when I remove the disposable pleated air 
filter, I believe the noise is associated with the way the filter is 
supported by the rigid plastic air box. I don't think the rattle has much 
to do with the injectors.

Jamming wedges of heavy cardboard between the air box and the passenger 
front fender and otherwise stabilizing the air box as much as possible 
resulted in only a minor improvement in noise level. It is still very noisy.

I explored replacing the entire air box/pleated air filter system with a 
generic conical pleated standalone, but adapting the available 
off-the-shelf conical units to the existing air intake tube did not appear 
easy. I investigated the stock of several FLAPS and found stuff that was 
designed mostly for Chevy/Chrysler/Ford intakes. The cost of experimenting 
was significant and would have required ordering correct diameter parts 
pre-paid which might not work anyhow, so I put off doing it.

I have seen the conical filters used on older Audi's which have stock air 
boxes that are very difficult to access, and on hot rods that required air 
filter adapters because the engine was not stock for the chassis.

I would welcome any information about how to eliminate the air intake 
rattle on my 85 Jetta TD, other than by running without an air filter. 
Maybe someone knows exactly where I can order a pleated conical unit that 
will fit.

Doyt Echelberger