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Discussion Starter · #1 ·
Hey guys, I’ve got an 05 LLY that doesn’t start well below 30ish degrees.

It cranks for a pretty long while (going until the starter cuts out 4 or 5 times) before it finally goes.

I replaced all 8 glow plugs a few months ago, but it still does this. I’m thinking the actual plugs themselves aren’t getting enough current. Haven’t load tested them though. If it keeps up I might see if I can find an intake heater for it.

Any thoughts?
 

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2006 LBZ, 2009 LML, 2022 L5P. 1993 6.5 parked in the shed.
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Are you getting any exhaust smoke during all this cranking?
 

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Cold weather really puts a load on the batteries. Charge your batteries overnight and see if the situation improves. Even relatively new batteries can have problems. I bought one that had a short in it and it took a while to figure out what was going on with the new and presumably good batteries. You really have to TEST when it comes to electrical problems. Don't assume anything.
 
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Have you got any codes that might indicate the glow plug control module is failed? Also, instead of an intake heater, why not just plug in heater?
 

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Discussion Starter · #5 ·
Have you got any codes that might indicate the glow plug control module is failed? Also, instead of an intake heater, why not just plug in heater?
No codes, but I’m at college in Montana right now and there’s no place to plug it in.
 

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No codes, but I’m at college in Montana right now and there’s no place to plug it in.
Ah, that sucks. The glow plugs on this truck work very well from my experiences. Even really cold -15 /-20 starts mine has always started on first crank. If the glow plugs end up testing out ok, how's the fuel and filter? Looks like you had issues in the past losing prime, pressure... ?
 

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Did you ever figure out if your lift pump was actually pumping fuel to the fuel filter? Loosen the bleed screw, and turn on the lift pump, and you should be fuel coming out of the bleed screw.
 

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2006 LBZ, 2009 LML, 2022 L5P. 1993 6.5 parked in the shed.
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If you're cranking that long it should make smoke if it's getting enough fuel. I've got one with 8 dead glow plugs that starts even at 0F...make sure it's getting fuel, and then, that it's cranking fast enough.
 

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Wasn't it the 07.5+ that got the smart glow plug technology and the older trucks just have the typical old style?
Also- what oil are you running?
What brand of batteries and how old? What are the CCA ratings on those batteries? How much driving do you do with the truck each day?
 

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try cycling the glow plugs twice, when the wait light turns off, switch the ign off then turn on again, wait till light is off and try starting
 

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Discussion Starter · #13 ·
Wasn't it the 07.5+ that got the smart glow plug technology and the older trucks just have the typical old style?
Also- what oil are you running?
What brand of batteries and how old? What are the CCA ratings on those batteries? How much driving do you do with the truck each day?
Running cat batteries 880 cca on the two of them. They turn over plenty fast and hold charge forever. Running shell rotella 15-40. Truck sits for a few days a week and then will run for a few hours during the day. I idle it to make sure it’s not constantly starting and stopping.
 

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Discussion Starter · #14 ·
Did you ever figure out if your lift pump was actually pumping fuel to the fuel filter? Loosen the bleed screw, and turn on the lift pump, and you should be fuel coming out of the bleed screw.
Lift pump is all good. Truck has perfect rail pressure.
 

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Discussion Starter · #15 ·
Ah, that sucks. The glow plugs on this truck work very well from my experiences. Even really cold -15 /-20 starts mine has always started on first crank. If the glow plugs end up testing out ok, how's the fuel and filter? Looks like you had issues in the past losing prime, pressure... ?
Considering I just did all 8 plugs, do you think the module itself is bad? Or is it some kind of wiring issue. My thoughts would be that if the module was bad they wouldn’t light up at all, but they do on the dash although I would put money on them not actually heating up.
 

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If it has fuel, and cranks fast, even at 15 degrees it will start well with no glow plugs at all. As mentioned by @Ottowood ,might be time to check for compression.
 
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Discussion Starter · #17 ·
If it has fuel, and cranks fast, even at 15 degrees it will start well with no glow plugs at all. As mentioned by @Ottowood ,might be time to check for compression.
Is there any way to check the compression without actually hooking up a compression tester to it and turning it over?
 
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