Getting frustrated with my 7.3

[Wetpavement]

I'm having starting issues. Since the weather started to change its been getting harder and harder to start my truck. I thought it was the batteries so I had them tested, they are ok. Checked the alternator, tested fine. So next I changed the GPR, no change. I've since bought new glow plugs to replace this weekend while I change out my exhaust manifolds. But Im wondering if its even the glow plugs. The temp has been about 30 at night and 50ish during the day. At night I've been plugging it in and putting the batteries on a charger because the constant cranking during startup is ridiculous.
I do let the "wait to start" light cycle twice before I crank and it just turns and turns. IF its plugged in and the battery charger is on, it will eventually fire after 2 - 3 attempts. With some white/grey smoke and a little bit of hesitation when I give it "gas".
Here is the reason I'm wondering if its the GPs. I can run my motor for half an hour, shut it off for minute and it does the exact same thing. If the motor is hot, would it even matter if both banks of GPs were junk because its already hot in there? lol Then it brings me back to the battery issue, if they test out ok and the alternator is working properly why does it seem like they arent holding charge?
I'm eventually gonna replace the GPs and batteries, probably this weekend. I suppose I'll see if that has any effect but I wanna check to see if anyone else has any insight. thanks in advance guys

[NoRalPh]

Couple things.....

First, that whole "cycling" of the WTS light is a waste. They actually remain ON for much longer than the light is illuminated.

Second, I'm gonna agree with you! If the truck's been run for a 1/2hr it's fully up to temp and should NOT be hard to restart right away. I would think you've got to have other problems besides Gps.

I would think about fuel delivery, HPOP drainback, maybe even injector issues,, I would also want to get a good scanner on the truck to know what's going-on with fuel & oil pressures (IPR ICP) when you are first cranking it over.

Is it turning over at a good speed? It's not slowly cranking is it?

[Wetpavement]

well Im NOT a diesel genius by any means but I'm learning. I just added a superchips tuner a few weeks ago that registers codes. I could see if it has pulled any and look them up.
Yes it cranks super slow, at night I usually plug it into a battery charger and also while I'm at work. I have also noticed here lately that the service engine light comes on and the motors sounds "starved" after I get on it to pass or go up steep hills. It usually comes out of that after a second or two. It really started doing that when I added the "FAI" my ignorant way of saying I have this 5 pos dial that is hooked to my turbo making it work harder.

[Bad Night]

When you had the batteries tested did you unhook them and test one at a time ? This is a must for accurate results .

[Wetpavement]

No, I took it to my cousin who works for the local Oriellys. He tested them while they were on the truck still chained together.

[Bad Night]

That doesn't work . You probably have a weak battery . Check them individually .

[Bad Night]

If they both test good then pull the starter and test it . Sometimes when the starter is taking a poo it draws so much power it pulls voltage from other important items . It's one or the other but probably the batteries .

[atvrider93]

i'm thinking batteries too.

[Wetpavement]

Well I'll do that in the morning then. but thats still not gonna change the fact that the truck wont start in 50 degree weather after running for half an hour unless its plugged in right? I mean sure I understand the whole low cranking thing and I have the glow plugs to change this weekend. What about the smoke at start up? Injectors maybe? I LOVE my truck and have so many things I want/have planned to do to it but this is frustrating. I'm starting to think I would rather listen to my wife nag about nothing all the time then have to keep dealing with this! lmao

[Bad Night]

Low voltage and it cranking slow can cause the bad starts even hot as well as the white smoke . When the motor is cranking slow it isn't gonna compress and burn all of the fuel .