[Vwdiesel] sparks out the tailpipe

[Sandy Cameron]

At 06:08 PM 10/12/2007 -0500, you wrote:  Anyway, the other night while
traveling in
>the country going to a nursing home with the church group to sing Christmas
>carols I was at the tail end of the line when a big truck came up fast
>behind me. So I was going 55 and punched it and ran it up to about 80, it
>was a long straight away. Well when I left off the gas I noticed a bunch,
>and I mean a bunch of sparks coming out of the tail pipe, some were pretty
>large in size and lasted at least 15ft or more behind the jetta until they
>went out.\\


Been there , done that, etc.

A) Since your rig breathes so well, it can throughput lots more air than it
needs for its own combustion, resulting in ann oxygen-rich exhaust system
when you let the pedal up.

B) Since you somewhat "baby" the car most of the time, carbon slowly builds
up on the inside of the exhaust system until a nice carbon "bomb" is lurking
in there.

Pedal to the metal for 40 seconds and high revs under turbo boost will get
the exhaust hot enough to ignite the carbon, and sudden cut-off of the
fueling will fill the ehaust system with fresh air (the turbo diesel at high
revs continues to flow (pump) air through the engine to feed the fire until
A)  the revs drop down, slowing  the air flow, or B) untill the carbon burns
out.

I think it is called an "Italian Tune up"

Sandy