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Discussion Starter #1
Hi guys looking for some help! Yesterday turning on my road my lly started to blowing a ton of smoke and knocking real loud..checked the known issues 2&7 connectors and the harness by the ficm and then I ohmed from the ficm to each injector plug and all of them where 0.1&0.2ohms so all good there...so I would unplug each injector and start the truck each time and thought #6 was bad but I replaced with a extra I had and it’s still knocking and thw truck is struggling to start...I should also add I pulled upper valve covers off last weekend and adjusted all the valve lash to .011 ran fine all week long back and forth to work till yesterday...if anybody has any thing I can possibly try Or to look for I would appreciate it!!
 

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sounds like a injector stuck open. you can unplug one injector at time if it clears up you found what one it is.
 

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Discussion Starter #3
Anyway it could be a bad ficm? I know they don’t go bad often i got a buddy who has a extra I thought about swapping over
 

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Did you try the "ice pick" fix? If not, search for it, it's a common issue on LLYs. If it's a "sticky" injector, before you start swapping injectors, try a dose of Hotshot's Diesel Extreme, if things quiet down you are probably just about ready for a new set but it might get you by for now. I had a knocky injector on my LLY about a year ago, tried the Hotshots Extreme and it's been quiet ever since. I know it's not a fix, some day I'll have to bite the bullet and replace them but it sure quieted things down and I was amazed at how that stuff restored power!!
 

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Wouldn't hurt to try the other FICM just to rule it out.
 

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Discussion Starter #8
I’ll go grab that ficm today and see if it changes anything I ohmed each connector back to the ficm and all were good do you think I need to ice pick them anyways?
 

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I don't see it hurting anything.
 

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Discussion Starter #10
Sooo got the truck to start and unplugged #4 and the loud knock goes away and the black smoke stops but it still has a spudder type knock that’s just from it being in tractor mode possibly?
 
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