So I bit the bullet and pulled #1 injector on the 81,
Looking down into the threaded collar there was a small amount of flaky soot under the insulator around the injection hole and I could see the GP tip further down but other than the greyblack color of that lower area there is no build up of soot or carbon.
The injector tip had no build up either.
Does this sound like normal condition?
I have not pulled the nozzle. Is this something that is necessary to determine whether it needs cleaning or would it be obvious?
Do I need to pull the threaded collar to see how things really are down under it??

__________________
1981 240D 143k 4 spd manual -SOLD

2004 VW Jetta TDI 5 speed 300k -still driven daily

That sounds normal. There is no way to accurately check nozzle condition by looking at it, only by checking its spray pattern.

__________________
1979 240D- 316K miles - VGT Turbo, Intercooler, Stick Shift, Many Other Mods - Daily Driver

1982 300SD - 232K miles - Wife's Daily Driver

1986 560SL - Wife's red speed machine

Why did you pull it? Was there a light light bulb looking thing under it?

__________________
http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42

If it has a Bosch Spray Nozzle in it look at the center of the pintle and see if the little hole in the end appears to be plugged up; item #15 in the pic.
Also see if the area of the Spray Nozzle that is exposed to combustion has eroded/burned away.

__________________
84 300D, 82 Volvo 244Gl Diesel

I have the car in the shop all winter and the few miles I drove felt like it was a little punked up . The PO drove it maybe 500 mi/yr for the last 10 and was notoriously light on the throttle so I suspected that maybe it needed more that an Italian tuneup to put some zip back in its step. So I decided to have the injectors tested.
Do I need to separate the nozzle from the rest to see the orifice or is it visible on the bottom end ?

__________________
1981 240D 143k 4 spd manual -SOLD

2004 VW Jetta TDI 5 speed 300k -still driven daily

I see no hole in the center of the end although it looks as though there should be

__________________
1981 240D 143k 4 spd manual -SOLD

2004 VW Jetta TDI 5 speed 300k -still driven daily

If you have a Magnifying Glass it might be easier to tell for sure.
When I pulled what were probably the origional Injectors from my car the little central hole was plugged.
The same with most of the Injectors I have pulled from the Junk yard.

If you are going to have them tested and the person testing knows what her or she is doing they will be able to tell.
When the person doing the Pop Test works the handle he/she has to work the Pop Tester handle to give short strokes to simulate an Idle quanity of fuel. The small quanity of Fuel will lift the Pintel up only enough that the Fuel should come out of that central hole.
After that they are Pop Tested like the Spray Nozzles without the Central Hole.

There is 2 Differnt Spray Nozzles that have 2 different sizes of Central Holes. The later version with the larger Holes has a / stamped after the numbers.

I found 1 of my pics. You can see the central hole and at lest this end of the hole looks open.

Attached Thumbnails

 

__________________
84 300D, 82 Volvo 244Gl Diesel