Hi Cal.

Have you ever had the valves adjusted?
If not it might be time to do so.
Have them adjust the valves and try the car
for a few days.
You'll notice a big improvement with the
valve adjusment and you probably don't need
the compression test.
Unless there is no improvement.
You don't say if the new glow plugs made any
difference.

If no change then this applies.
Yes it does make sense to do a valve adjusment
first,because if one or more valves stay open
or closed you won't have any compression.
Just like trying to blow up a ballon with a hole in it.


The glow plugs most likely went out because they
served their purpose and deserve to be retired.
(it they where the originals).
But 5 secs preglow isn't enough.
Do you wait for the glow light to go
out?
If not,you're cranking to soon.
Also try to cycle the glow plugs two or three
times.

Louis.