2002 F-350, 7.3 Power Stroke. 292K miles.
It wont start. Turns over great. At first few revolutions it sounds like it is about to start, then just rotates. Vapor can be seen flowing out of the exhaust pipe. Fuel bowl was drained and it refilled. Don't know what kind of fuel pressure I have, can't see where I can connect a gauge. I did a buzz test on it. 2, 6, and 7 are very wimpy sounding, 8 is non-existent. So I am leaning toward injectors. This truck has been real hard to start when cold for a few years. I have had in the shop a few times and paid to have injectors replaced in 3 places (don't remember which three so I have to call that shop and ask). No one seems to know why it is so hard to start. I have had to replace the ICM twice. Even when I do, my auto enginuity computer tells me the is an ICM error, but no details. Apparently, there are no trust worthy diesel mechanics in my area. This is a great truck that has been real good to us, even with its problems.

Before I tear into this, can anyone suggest an alternative route? Also, any suggestions on where I can purchase GOOD rebuilt injectors? I'll do the glow plugs at the same time.

 

Just shooting in the dark here, but have you thought about your glow plugs? I also assume you don't have a heater to plug in at night to keep it warm.
I'm going on the experience of 2 older 7.3L diesels, one was a 1990 and the other was a 1994. The 90' was taken to Florida from Illinois, and for some reason after awhile it got hard to start. The truck was taken to the local Diesel guy and he said it needed to have a hot pack installed, don't know what that is but it worked.
On my 94' F350 I had the 7.3L IDI Turbo, it kept getting harder to start as it go colder, I did 2 things at the same time so not sure which was the actual fix, but, I changed the glow plugs and I changed the O-Rings on the injectors because I found one leaking and I never had a problem with it starting again.

 

Thanks Mike. I did, briefly, think of the Glow Plugs. But I was being distracted by the buzz test. I am not sure what to listen for, but there was a definite difference. I do not have much experience with diesels so some of the tasks are a little intimidating. I guess I just have to shot gun this and do the things that I suspect are needed anyway, such as glow plugs.

Any body else have some input?

 

Definitely look at the glow plug system, specifically the glow plug relay first and foremost with your mileage. It's an easy test with a multimeter or a test light. With a meter you should see a significant voltage drop as soon as you turn on the key. With a test light you should see one side of the glow plug relay hot (the big posts) all the time and as soon as you turn on the key the other side should light up.

 

Need crisp sounds coming from all those injectors -- you're on the right path .

 

OK. I replaced all of the glow plugs. Not the right answer yet. I am not unhappy about the glow plugs since they probably needed it anyway. While at it I also checked the glow plug relay. I don't know how to test the fuel pressure or oil pressure. If the oil pressure is too low then the injectors wont fire. But then we go back to the buzz test with the 3 weak ones and a no show on number 8. This truck has run like crap for quite a while now. It has to be started a half hour before driving because it runs so bad while cold. Since the first freeze it wont start. Who here does NOT think it is injectors? If not, then what? If I spend the money on injectors, then find out that wasn't it, I wont have the money to spend on the it. Well, it would be harder anyway.


I have the AE computer. If there is something there that I can use to trouble shoot please tell me about it.


Thanks everyone.

 

looks like with those miles it might be your injectors, read this.
hopefully the link works or copy and paste it. I couldn't see a way to attach it as a pdf file.

https://www.google.com/url?sa=t&source=web&rct=j&url=https://swampsdiesel.com/files/7.3LInjectorDiagnostic.pdf&ved=0ahUKEwjq5MSh3q3YAh VG4YMKHdjSCYYQFgjyAjAC&usg=AOvVaw1OhdP6L9IfQs_0Yxg J8eYh