[Vwdiesel] 85 Jetta TD Air Filter Noise FIXED
Doyt W. Echelberger
doyt at buckeye-express.com
Wed Apr 26 18:29:06 EDT 2006
Rejoice with me. The conversation-stopping rattle from the air filter box
is FIXED! The noise puzzled me for at least 10 years and I could only stop
it by taking off the lid of the air filter box and removing the air filter.
Without the filter or the lid, the noise was gone. I couldn't run that way,
so I just ignored the noise and accepted it as a characteristic of driving
this wonderful car.
Big mistake. Should have looked deeper into the system of how intake air is
ducted from inside the passenger front fender into the air filter box.
Maybe some of you are living with the same problem.
After adjusting the solid valve lifters today, I was leaning on the
passenger fender, listening to the engine idle and looking for valve cover
leaks, when I noticed that the rattle seemed more associated with the
fender than the air box. I ran my fingers down the inside of the fender, to
the point where the tube from the air filter entered the fender. The plate
on the fender that sealed this union was vibrating as though a tiny hammer
was inside, pounding away.
I twisted the tube where it entered the fender, and was able to get one
finger inside the fender. I felt a plastic plate about 4 x 4 inches, and it
was being sucked up against the entry tube like a flapper, making the
racket. AHAH !! Ten years of mystery about to unravel.
The tube went into a plastic box that was located inside the fender. It
was sort of like a rectangular box that electricians use to protect
junctions. The curbside wall of the box had come loose from the walls that
were designed to hold it away from the entry tube, and it was trying to get
into the air filter and participate in the combustion process.
I took the system apart and spread the parts out on a towel, and decided to
simply eliminate the offending plastic wall rather than trying to repair
the "junction box." The noise is gone, and so is the back wall of the box
in the fender. I'll probably take it apart in a few days and figure out how
to restore the original integrity of the fender box, because it certainly
has something to do with keeping water out of the intake. But for now, THE
TEN YEARS OF NOISE ARE GONE. An era is over.
So I rejoice....with some embarrassment at having put up with it for ten
years. It probably also cut down my engine efficiency. ....considerably. I
thought the engine was just getting old. Pictures of the offending plastic
plate and the entry tube that goes into the fender are available on
request. If a web site could display them, it might help somebody.
85 Jetta TD.................. now quieter
More information about the Vwdiesel