Originally Posted by rick.whitaker65
I replaced all the glow plugs and the glow plug switch. The truck will not start unless plugged in during cold weather. In warm weather if you don't let the truck warm up for 20-25 minutes when you drive it it will not go over 30mph for about 2-3 miles. Then it gains full power and takes off.
Replace your Exhaust Back Pressure Sensor and tube.
Passanger side exhaust manifold, front. You will see a tube that runs from there to the front of the motor. Replace that tube and sensor.
Your issue will go away.
As far as the truck not starting when cold, sounds like the glow plugs are still not working.
Check this link, might help with the diognostics...