I have a 2002 Focus 1.8 TDCI estate that just won't start without a fight.

The glow light comes on for about a second when i turn the key, the glowplugs will have 12v a few seconds after the light goes out. It doesn't matter if it's +5 or -20 outside.

I tried removing the fuse and relay for the glowing, and the light still lit up for about a second. (obviously the glow plugs didn't get any current)

The glow plugs was replaced about 2 weeks ago due to one of them was broken.. not only defective.. BROKEN so that it shorted out and took the fuse (60amp) with it when it died.
I also tried to replace the glow relay, still a no-go

If i use the heater for a few hours it's easy to start..

Any suggestions is appriciated, the whole ordeal is driving me sane ...