[Vwdiesel] New Engine Smokes

[Gavrik Peterson]

As you guys may remember, last summer, after lots of fussing around, I
completed installing my rebuilt 1.6 litre NA engine into my Rabbit.

For the first 3k miles it appeared to be running just fine, with very
good mileage and low smoke.  The only time smoke was visible was when
driving at night with a closely following vehicle.  If I accelerated
hard at high RPM, smoke would be visible because it scatters the light
from the following vehicle.  This was is a very sensitive test for
smoke, so I was completely happy.

Around 1500 miles ago, suddenly, it started to smoke way more under
the same conditions, and smoke could be seen in the daylight.  When
this started to happen, Hagar suggested replacing the nozzles which
had around 100k miles on them.  Now I have new nozzles and adjusted
injectors.  Although testing of the injectors showed that they needed
to be rebuilt, this did not effect much change.

Before the smoking started, I got over 49 mpg with highway and some
city driving.  On a recent highway only trip, where I maintained 60
mph, I got only 41 mpg.

Here is more detailed info.  When I first start and idle smoke is
easily visible by just looking at the exhaust pipe from behind.  As
the engine warms up this goes away.  It did not do this before.  So
whatever is causing the smoke, occurs at idle RPM.  When driving
around the engine sometimes smokes visibly with only moderate
acceleration and RPM.  Another thing is that the engine does not sound
as good as it used to.  This is most noticeable when driving on a cold
engine, where it sometimes sounds like a spark ignition engine that is
knocking.  This is different from the way is sounded before when cold.

Are these well understood symptoms?  I am going to check the valve
clearance and timing and the pump timing.  Not sure what else to focus
on besides having the pump tested.

  --  Gavrik