Crank NO Start 2002 2500HD LB7

[dgalvin66]

I have a 2002 GMC 2500HD LB7 with a Crank NO Start problem.
This happened about 4 years ago and turned out to be the filter head. I just replaced the filter head, filter and the 2 fuel lines coming of the housing and it still does not start.
I have a basic code reader that is showing no codes. I know someone that has a Tech II scanner and trying to find time for him to come over with it to see if it tells anything.
I do NOT have the money to just start throwing parts at it in hopes that something will fix it. Please tell me what to check and how to do it to try and determine the problem. What tests to run when I get the Tech II here?
Thank you

[a5150nut]

Diesels need air, fuel, and compression to run. You said you had filter problems. have you confirmed fuel in system and not air locked? Did you bleed the system?

[DmaxMaverick]

If the injectors aren't firing, for any reason, or it's unable to develop sufficient fuel pressure to fire them (if the system is primed), it WILL set codes you can read with a basic code reader. If you've replaced the filter head (or just the filter can), it must be primed, as well as pumped until fuel primes all the way to the high pressure pump. It will not self-prime. Open the bleed screw, pump the primer until fuel is present at the bleed hole, reinstall the bleed screw, and continue pumping until it's hard. It may take a LOT of pumping, like a hundred or two strokes, in some cases. Crank for about 10 seconds, pump again until hard, and repeat this until it starts (don't hurry, let the starter cool). It may take several of these cycles. It's important to have sufficient battery voltage, so have a charger (or a jump vehicle) handy if it shows any sign of slowing down while cranking.

[dgalvin66]

I did correctly bleed and prime the system. I even went back out and did it again, I have a strong steady stream of fuel coming out the bleed screw and after tightening it I pumped a few times until hard. I have a full tank of fuel. I replaced the filter head because the last time I had a no start issue this was the problem. I did not find the old one to be leaking but swapped it anyway.

I purchased a bluetooth OBDII and downloaded some scanning apps onto my tablet. I'm not sure of what to be looking for but I did get a little info.
Desired Fuel Pressure 6090 = Actual Fuel Pressure 5960
Fuel Pressure not running is 145 psi
I pulled a few codes that my reader did not get.
U1000
B2961
B2973
B3138
Does any of this help with figuring this issue out?
what tests can I do to test the FICM or ECM and Injectors?

[a5150nut]

A quick search of your codes is computer communications and key/door lock electrical related

[jhornsby3]

I too had this issue a couple of years ago. Rebuilt the filter head because it was leaking internally. When my injectors were replaced a year before that, all hoses were said to have been replaced. Of course they didn't replace that $140 9" hose with that special bend in it. At that time, I would have all the dash lights (instrument cluster, radio, hvac system ect.). Mine just started this yesterday. Cold, she fires right up. Drive it and get to operating temp and won't start at all. Pump primer and crank, it tries to kick off then nothing. Rinse and repeat. Now, here is the kicker. As of yesterday, when I turn the key to the 'ON' position, nothing comes on. Only one light (battery) comes on and stays on. It's not until I release the key from Start that the dash will light up for a nano second. Just a quick flash. I put my Innova 3100 scanner on it and there is zero "common" codes. If I run the Chevy SRS codes I get U1042 'Loss of EBCM Comms' and a U1000 'Class 2 DATA Link Malfunction'. When I scan the Chevy OEM Enhanced codes, I get a U1041, U1026 'Loss of Class 2 Comms with ATC' U1152 "loss of ACM Serial DATA Comms', P1626 "Theft Deter Fuel Enable Signal Not Received', P0380 'Glow Plug Circuit Performance' and U1096 'Loss Comms with Instrument Cluster' codes.

I can clear the OEM codes as those are a stored "history" of codes. Wait about 5 minutes and the dash lights up and hit the key, fires at the second turn of the crank shaft (normal). This tells me I have one problem and one problem only. Not have an issue and than after a crap ton of rain (several inches a day for three days, four nights straight) is I have a grounding issue. No communication with the ECM, has to be a ground is dirty and not making the proper contact.

Does this sound off to anybody?

[a5150nut]

with weird or random electrical problems the first place to start is battery connections and then grounds. Check cables that they are not rotted internally

[jhornsby3]

with weird or random electrical problems the first place to start is battery connections and then grounds. Check cables that they are not rotted internally

Yeah, I got to the battery side of things because they were easy to get too with all the liquid sunshine we have been having. My plan is to get to the other ends after things dry out for a day (today). Went from heavy showers and 40*(yesterday) to 70* and cloudy today. About 75* tomorrow. Thats is the perfect weather to have ones butt sticking up in the air while bent over in the engine bay.

Maybe my issues that are very close to the original poster's issues are similar enough to help him out.

[dgalvin66]

Had to take a bit of time from the truck for health reasons.
I had done nothing to the truck other than drive it, I did replace the water pump about 6 months prior.
Here is what I have tried as time and health have allowed:
1) I disconnected the Input fuel line to the filter head and connected a long fuel line with a fuel pump and ran that into a 5 gallon gas can with fuel in it to see if it could be a problem with some of the fuel lines sucking air, that did not help any, so I put it all back to stock.
2) Today I disconnected the power to the Glow Plugs and sprayed starting fluid into the air intake and got it to fire up, just long enough to use what I sprayed and quickly died. I did not want to do that too many times, so I am done for the day.

I did replace the filter head housing when this problem first started hoping that was the cause, I guess it could have been a bad replacement part, so I am thinking to replace it again after reading so many posts about the Doorman parts being bad right out of the box.

What are some thoughts and ideas on what to try next?
Thanks

[a5150nut]

Did you prime the filter? My filter head had developed a small leak and would allow air in. When trying to start sometimes I had to pump the primer and bleed the air out. Replaced filter head and solved that problem.
Then Water in Fuel light started randomly coming on so I replaced that. Now it only lights up when its cold but no water in fuel. Summer has been fine but now we are getting in th low 50s at night it lighting up again.

[dgalvin66]

I believe that I got it primed, had to pump it over 100 times and loosened the screw a few times to bleed it. I is getting soft again after trying to start it with the starting fluid and I have to pump again.

[DmaxMaverick]

I believe that I got it primed, had to pump it over 100 times and loosened the screw a few times to bleed it. I is getting soft again after trying to start it with the starting fluid and I have to pump again.

100% normal, except for the not starting part. If it's lost prime, it can take, literally, 100 or more pump strokes to get it to harden. When you crank it, the HP pump draws fuel from the inlet, dumping that pressure you pumped up (and you have to do it again if it doesn't start). However, after this, it should pump up in just a few strokes. If it takes a lot of pumping again during the later attempts, it's sucking in a LOT of air, from somewhere, preventing the HP pump from priming, and unable to create enough pressure for a start. The LB7 requires 4000+ PSI before it will fire the injectors (and the reason for the long cranking, which is normal). Leaks that suck in air don't always leak fuel out under pressure. The opposite can also be true.

[DmaxMaverick]

Oh, and stop using starting fluid. That stuff is for emergency use only. If you've tried it a couple times and you still don't have a start, quit using it. It is NOT helping you with anything, except increasing damage risk.

The LB7, when healthy, starts easy, and doesn't require glow plugs, under most conditions. They are there for extreme cold climates, and to keep the EPA happy. I've tested a few cold starts back in 2007 when I made a trip north in January, after overnight cold-soaks, with the GP's disconnected. It started at +8F almost normally, with only a couple seconds of rough running. The -10F and lower attempts were quite a bit more rough for longer, but it started, every time. I actually drove it for several years with failed glow plugs. I don't know when each one failed, but when I finally replaced them, it was down to only 1 working plug, which is a factory original, still installed and working today (it will quit tomorrow, now that I've said that).

Bottom line:
If you aren't getting it started on just fuel, and especially with the ether help, you need to find out why it isn't firing. If you're having an air intrusion issue, nothing will work until you fix that. If it's getting fuel, make sure it's really fuel, and not something else, like a bunch of gas in the tank. Sill things like that just happen, from time to time. Years ago, my wife made a habit of filling the Mercedes Diesel with gas. No real biggie, but you can't ignore it.