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Discussion Starter · #1 ·
Well I am back again with more problems then what I started with. Long story short I ended up pulling my motor out back in January due to a water pump impeller destroying my front timin cover. I ended up replacing just about everything from injector cups,hpop,lpop,turbo,glow plugs,water pump,injector orings,etc. well I am back to square one and have diesel back in my coolant and most recently it started knocking at idle on and off. I pulled the valve covers yesterday and could not get it to make the knocking sound again. Ended up doing a compression test which came out at 380-400psi across the board with the exception of cylinder 5 being at 345. I also checked the resistance on the injectors which did not come out very well I only have 2 injectors that are below 5 ohms most were close to 15ohms with one as high as 50ohms. They have 210k miles on the injectors but the uvch were both replaced 50k miles ago. The knocking seems to be worse in the cab.my first thought was the torque converter or cracked flex plate. But unsure how to diagnose it. If I pop the hood and look in the hood an wheel well it's not nearly as loud as it is in the cab and it only seems to do it at idle after going up a hill. It also does it if I shut the truck off for 5 mins then go and restart it. It will knock for about 2-3 mins at idle and then go away. Any one have any ideas I may be over looking. I know I need new injectors but would a bad injector knock louder at idle randomly. I've even ran a CCT on AE and it won't throw any codes at all. I would think it would be much more consistent if my injectors were the root cause of the knocking. My biggest concern is an injector was over fueling on cylinder 5 and cause some unwanted wear on the lower end and valve train.
Thanks ahead of time for any help
 

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Sounds like injector knock from the #8 injector. Mine knocks really good at idle when it's cold
 

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Discussion Starter · #3 ·
Damn wasn't sure if you were still floating around on here. I knew you helped a bit when I was trying to fix my low boost problems after I did the cups. Completely forgot about the #8 injector being an AE injector. Not sure exactly what all is different inside of it that would make it knock more then the others other then just extra wear from the dead head. I even believe that is the injector that has crazy high resistance. I also have a ****ty power steering pump that keeps making a loud humming noise for the last year or so that I thought would be the culprit but I just cannot hear the knocking in the front of the motor. And the 38r isn't making it any easier to find the knocking. Guess I'm just gonna have to dive in and hope for the best with new injectors at this point since I know they need replacing.
 

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Been busy at work lol

I'd hold off just yet on replacing the injectors

The reason it's knocking is because it gets less fuel and oil than the other injectors.

I would try a high pressure oil crossover and some type of fuel system mod like riffraffs frx or cncfabs 4 line feed kit. The fuel mods usually solve the issue but the hpx helps stabilize oil pressure and spikes between the heads.

Have you tried flushing the power steering system? Some good synthetic atf really cuts down on noise
 

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My Power Steering Pump quieted down after a thorouh flush and fill with Valvoline MaxLife Synthetic.

Good luck with the knock.
 

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Discussion Starter · #6 ·
Yeah I hear ya with work . I was gonna go with the CNc 4 line kit when I upgraded to 160/30. Guess it wouldn't hurt to do it before hand I guess to rule out dead head issues. And be ready for new sticks in the future.I'm still thinking it's gonna be more then a fuel issue. I'm assuming the high resistance in all my injectors is just saying my solenoids are bad. Does the mechanical part of the injectors go hand and hand with the solenoids as far as telling me what condition the internals are in? I've kinda been under the assumption that most of these injectors hpo side typically only last 200k miles before they start causing problems slowly but surely. I have been getting terrible mpg and a ton of black smoke aswell if I get into the throttle. Even has a slow throttle response when just cruising.

As for the hpx or hpo x over line. I think I'm good there with the new adrenaline HPOP. Supposedly they drill the pump body or something to equal pressure in each head so they say.

I already swapped the ps fluid out to synthetic atf awhile back.The way it sounds at this point is worse then when I even had regular non synthetic in it. Tons of noise and most recently some slight grinding and the brake pedals is starting to feel a bit hard. Figured it's a cheap replacement at this point but I'll be sure to flush the old oil out and replace it with fresh synthetic atf again the noise benefit was incredible when I first made the switch.
 
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