[Vwdiesel] What makes an injector stick and make a sound like you have bl...

[James Hansen]

Naw, Andrew is right Bryan.
A stuck injector with no spray pattern makes a dandy high pressure 
piston drill.
Rev the motor? Maybe just once or twice, but it usually is not a clear 
out the bugs/ Italian Tuneup issue, it's got some varnish stuck to the 
pintle, or a speck of gunk or dirt attached to same holding it open.

The first time it happened is a warning to have a look.  Second is the
injector calling you by name loudly. Third time is the injector doing a 
pole dance to AC/DC's Sink the Pink with you in squatter's row.  Time to 
R&R at the very least the bad one.  At some point it will stick and stay 
stuck when you are miles from home on a deserted road late for an 
important meeting, tool kit left at home in the shed, extra injector and 
socket loaned out, and a dead cell phone with the car charger in the 
other car.

Injectors are CHEAP compared to a motor.


> Still wondering why stopping the motor clears it up
> and it does not happen again for a long time?

if the problem is varnish on the pintle, the OD of the pintle gets 
bigger due to varnish.  When things cool, it unsticks when it cools and 
shrinks.


> As always in my case, no easy fix here, but I will
> shut the motor down as soon as it happens, as I have
> been doing.  Again, it has not ever happened under
> load on the highway, only while coasting to a stop.

You won't hear it very well under load.
Plenty of neighbors notice this has happened to an injector on their 
tractor engine when the power drops off, and the crankcase vent starts 
to blow more smoke than the exhaust pipe.  No miss, no sputter, just a 
stuck injector that is overfueling with waaaay too much advance, 
therefore running hotter than the rest, enough so to dig a hole in the 
piston directly under the injector in a direct injection motor, or under 
the precup on an indirect injection motor.
> 
> 
> Well, I will keep this as food for thought.

Feast well, for tomorrow you may walk.
-james