Outer Limits 4x4 Board

i have a 99 gu coil cab with a 4.2 turbo diesel in it and it runs ruff when started cold check glow plugs and they where ok but replaced them anyway. still not good, but if you glow it 3 to 4 times before you start it it starts fine? is this some sort of current of glow cycle time problem ? any help will be great thanks. mango

Thats odd as the glow circuit on those vehicles should remain powered after starting for 10-30 seconds depending on temp, I'd be looking at the temp sensor.

Joel