nope the truck starts when plugged in, if i start it with ether what will that tell me

 

well that would mean the glow plugs are bad if it starts cold with ether

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I guess another thing is does it always have to be plugged in to start? or just the initial start of the day?

 

it has to be pluged in for the initial start of the morning i have turned it off and let it sit for half an hour and it will start again no problem.

 

yeah, i'm going to say it's the glow plugs, but I cannot guarantee anything because I do not know much about PSD's

 

I know it's a little late for a response. But I had this same problem a few years back. My 7.3 would not start under about 25F. It's most definetly the glowplugs. I want you to try something first off.

Turn the key and wait until the wait to start light disappears. Instead of starting it like usual, turn the key off. Turn it back on and do the same thing. Do this about 3 or 4 times. That might work but I'm not exactly sure. It did for me. I bought Bosch glow plugs and it's started as low as 5F without being plugged in. I try to plug it in though when I know it's going to get below 20F just to be safe.

I hope I helped!