Only starts when you use the "startup" spray into the air intake or the truck has been running for awhile and is turned off for a 30mins or so. What could be the problem?

 

30 minutes after it's fully warmed up?? Sounds like a glow plug issue.

 

Yeah, it warms-up and then it will start with some hesitation. Otherwise, overnight cooling down or a few hours, cranks but no start.

 

Check your glow plug relay. The 7.3's have issues with the relays failing. The relay should be energized for about a minute after you turn the key on. Use a test light to check for powers and grounds. If thats ok then your injectors might be worn out. What is the temperature the truck sits in? Do you plug in the block heater? How many miles are on the engine?

 

check fuel filter too.

 

Yea sounds like glow plugs but i had a costomers 6.0 do that and it was a valve in the fuel filter canister that went bad and after a few hours all the fuel would bleed off.

 

250,000 miles, new fuel filter, temp is from 50 to 85 degrees the truck sits in.

The truck fires-up with some hesitation when starter fluid is added into the air-intake.

Thanks,
Ryan

 

Have the injectors ever been replaced on the truck? Sounds like it might just have worn injectors. Make sure your fuel pressure is in spec. If the fuel pressure is at spec I would feel comfortable suggesting injectors if they have never been done.

 

What would you say it's going to run to replace the injectors?

Thanks BTW.

 

dont use starting fluid thats a good way to blow a head gasket. i would check your glow plug relay and if that doesnt fix it i would change glow plugs.