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Discussion Starter · #1 ·
I just replaced all injectors in my 2003 lb7. I took my time with everything and made sure all bolts were torqued to spec. I was so excited to get her fired up after a couple weeks of it sitting(did most of the work on weekdays after work). Opened bleeder screw, turned ignition for airdog to prime. Sprayed fuel everywhere, tightened screw, cranked for 10 secs. Loosened screw and primed it at the housing. Cranked again. Got it to start for less than a second and it just does the same thing everytime. It cranks for a few seconds then starts and dies in less than a second. I put a test light to glow plugs after turning key on. they have power for a few seconds then the light shuts off. That's how it should be right? Also I know I have plenty of fuel. But it sure seems like there's zero fuel. Please help me. Please!
 

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You need to check your lines. From the tank to the lift pump and forward, make sure you have rail pressure, FICM.
Check your injectors and glow plug connectors.
Are you tuned and did you update recently? Are they stock injectors?
 

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Discussion Starter · #4 ·
I just have the airdog 2 4g 100 gph lift pump and a sinister diesel cat fuel filter adapter. I had had diablosport tuner hooked up to it like a year ago, one that plugged in to the obd2. My cousin put the 100 hp performance tune on it. I borrowed that tuner back from him to remove the tune because I felt like it was actually having less power but it wouldn't let me!.. I think the tuner was saying my vehicle is not supported or something similar. But it started instantly every time ever since I got it in 2020. Just smoking bad so I took it to a diesel specialty shop and they said injectors were all terrible.. and yea they were all clogged.

I can't take the truck anywhere now of course so I hope you guys can pull me through this! Tried again this morning and it cranked for 4 or 5 seconds then starts and dies in under a second. I'll try fuses and all lines first, thanks!
 

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Discussion Starter · #6 ·
Thank you for that. There's alot I can try I see...

So far I've checked all fuses and they are good. I changed the fuel filter and put fresh fuel in it. Primed the air out. I tried to start a few times. Each time I go open the bleeder and close while the key is turned on for the lift pump to prime it. No air comes out, just fuel spray. I got under and primed the airdog fuel filter too just in case? Also with the pump on I got under there and looked and listened for any leaks. I got nothing. I just don't get it! I followed all the rules! Everything is plugged in exactly the way it was! The injectors are brand new from LDS. Bosch. Wife was pissed that I spent that much money on "that POS truck". And of course I tell her it's gonna run perfect and smoke free after this and now I'm just a fool. Idk. I'll try to borrow some of these special tools I guess. At this point I can't take it to a mechanic and sink even more into it.

If you know of any small things I could try that I may have missed, please help. I know I followed all torque specs and took forever on every step because I knew I didn't want to tear it apart again or mess up the huge investment on the injectors.
 

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Check the shrader valve by the alternator if that one has fuel you should be good on fuel. If all fuses and connections are good. check for codes even if the ses light doesn't come on, a code could be pending. The Ficm had to come off and if water/ moisture/diesel gets in it the truck could do what your describing sometimes a no start. a bent pin in the ecu or ficm connections could be possible.
 

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Discussion Starter · #8 ·
I just found out The Schrader valve shoots fuel like a garden hose! I will try to get ahold of a scan tool somehow. So can I go through the VATs steps even if the dash doesn't show the anti theft light? Also, the blinking light under the cd player... that stops blinking when I turn the key.. or maybe when I put the key in ignition but other than that it blinks all the time. Also normal? Right now I'm charging the batteries just in case somehow there's not enough amps to fully start it😶
 

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Discussion Starter · #9 ·
OK it wasn't that... I noticed everytime I try to start it, after i hear it poof and try to start, the security light turns on one the dash for a second then shuts off.
 

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Discussion Starter · #10 ·
Could my keyfob effect no starting? I mean it hasn't worked for a long time and truck has ran fine but the batteries were never disconnected since it went bad and during this injector swap, they were disconnected for a couple weeks.

I'll keep updating until I can fix this. Thanks for any help
 

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Discussion Starter · #12 ·
Thanks Ron. I've thought about trying that but my security light does not stay on for more than a couple seconds. I may have to charge the batteries and try it tmw anyway.
 

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Discussion Starter · #15 ·
It really helps having someone to help you with this stuff. My brother was over so I had him crank it over0 while I watched on the passengers side by the filter. He cranked and I saw fuel squirt from the number 5 pressure line on the rail. Tightened it up to 30 ft lbs and had him crank again. It tries to start faster now. Cranks only a second or 2 before going poof. Better than the 5 seconds of cranking before. I'm gonna tear the passengers side hosing and crap off tmw and see if I just forgot to torque more lines over there. 🙃
 

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Discussion Starter · #16 ·
Got the lines tightened on the passengers side. It was only the cylinder 5, the rest were torqued. Truck still just cranks and does a half start right away then shuts off. My batteries are pretty much dead. I've been jumping it when it won't crank. So desperate to figure this out. When hooked up to another vehicle of course it cranks fine. Would the batteries being charged make any difference? I mean it seems like it has to be a fuel problem. My buddy hooked it up to his snap on scanner. No codes except an old glowplug relay one that was there before and I replaced 2 years ago.

Could I get a fitting for the Schrader valve to plug my air compressor to and set it to whatever psi and spray soapy water on the lines to check for leaks? Would the FPR be a possibility? I may just throw some cheap parts at it. I really just don't want to bend over and have it towed to shop. I used 50% ether starting fluid and it started all clankity like for 2 or 3 seconds. I won't do that again. Sounded like the engine begging for mercy. What else can I check?

Thanks
 

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Your first purchase should be a battery charger.

What was the fuel rail pressure while cranking? Your friend's scanner is the best tool you could have in your situation.
 

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I think you got moisture either diesel or water in your ficm. Does it have the breather plug covered could happened during installation or disassembly. I would take the hour or two to take it off and clean it off dry it off on the inside. You can use a blow dryer. Charge your batteries and you can disconnect the glow plug module while cranking to save the batteries from draining while you try to start it, it doesn't need them if its not cold out.
 
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