Are you sure your glow plugs are coming on?
You do realize that using starting fluid in these motors can cause damage to the glow plug system.
I would start by bypassing the glowplug control and doing it manually.
Issam is right though they are super sensitive to air in the system. My fuel pump was leaking just a bit and it made it very hard to start
It don't hurt the glow plugs none -- What it hurts is the intake when it explodes
