If your getting air in the system it will make the truck difficult to start, cracking a line or two at the head will help to bleed the air out of the system while cranking. I would really suggest looking into the problem rather than dumping ether into your system, its just not good on the top end of your engine, or injectors. All those parts need the lubrication from the fuel and the ether wipes that out. Not to mention if its cool enough for a grid heater to light off, your going to cause MAJOR damage. Your also taxing your batteries and starter for no reason. Not trying to criticize, just offering my opinion. Get all your grounds checked, check the connection at the ecm, if your batteries are at all suspect, at a minimum I would put a good charge on them but is best to load test them, and go from there. Next step will be checking for voltage coming out of the ecm to the lift pump, and crank sensor.
Also, if you have access to a good code reader that may be helpful.