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Injector 1,3, and 8 are out of spec if you checked in Park and 1 and 3 are still out if that was an in gear test. How big is the fluctuation in pressure at idle? That can mess with the balance rates but I am not sure it would make #3 that much out. In my total rookie opinion it needs injectors again because #3 is putting way too much fuel in.
 

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Discussion Starter · #4 ·
Injector 1,3, and 8 are out of spec if you checked in Park and 1 and 3 are still out if that was an in gear test. How big is the fluctuation in pressure at idle? That can mess with the balance rates but I am not sure it would make #3 that much out. In my total rookie opinion it needs injectors again because #3 is putting way too much fuel in.
Hey i posted fuel pressure variance
 

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Discussion Starter · #5 ·
Injector 1,3, and 8 are out of spec if you checked in Park and 1 and 3 are still out if that was an in gear test. How big is the fluctuation in pressure at idle? That can mess with the balance rates but I am not sure it would make #3 that much out. In my total rookie opinion it needs injectors again because #3 is putting way too much fuel in.
Fuel knock
 

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After seeing the video I’d wager #3 injector is causing your knock. You said they were just replaced… where did you get the new ones from and did you change your high pressure lines when doing the job?
 

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Discussion Starter · #8 ·
After seeing the video I’d wager #3 injector is causing your knock. You said they were just replaced… where did you get the new ones from and did you change your high pressure lines when doing the job?
Previous owner did them my mechanic thinks it’s a failed cam ... I’d actually be happy if it’s just injectors luckily it happend in a parking lot
 

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my mechanic thinks it’s a failed cam ...
Yikes! That is something I don't hear about often. I will keep my fingers crossed it's something simpler than that.
 

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Discussion Starter · #10 ·
Yikes! That is something I don't hear about often. I will keep my fingers crossed it's something simpler than that.
It still runs and no engine codes so I don’t know if I believe it could be a cam ... how could I test the injectors to see ..
 

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It still runs and no engine codes so I don’t know if I believe it could be a cam ... how could I test the injectors to see ..
That balance rate is the only test I know of but that won't rule out the cam or something else. It could be showing the ECM trying to compensate for a different issue. If it were mine, I would pull the valve covers to see if you can tell what the deal is or run a compression check. You might see a valve, pushrod, spring problem under the cover there that the injector is trying to compensate for or the compression test may show you why #3 is dumping fuel to keep it going.

If it were mine and I could afford it though, I would just take it to a shop I trusted and wait for the bill lol
 

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Discussion Starter · #12 ·
My mechanic is pretty could I’m just wondering if I could swap #3 with a different bank see if the 15 changes bank then I’d know it’s injector
 

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My mechanic is pretty could I’m just wondering if I could swap #3 with a different bank see if the 15 changes bank then I’d know it’s injector
That would answer your question but it is a lot of work to get one out and replace it. If it is that injector it you will have that labor X2 to put in a good one. That's why most folks just change them all while they are at it. For what it's worth, my truck is broke down putting fuel in the oil right now and I am looking for any excuse to not buy injectors myself lol.
 

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Discussion Starter · #15 ·
I’m waiting on receipt from previous owner ... trucks getting ripped apart anyway was wondering if it’s safe to start without valve covers on for just 10 seconds to get balance rates
 

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Discussion Starter · #16 ·
That would answer your question but it is a lot of work to get one out and replace it. If it is that injector it you will have that labor X2 to put in a good one. That's why most folks just change them all while they are at it. For what it's worth, my truck is broke down putting fuel in the oil right now and I am looking for any excuse to not buy injectors myself lol.
Also trying to find out if previous owner did the lines
 

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I’m waiting on receipt from previous owner ... trucks getting ripped apart anyway was wondering if it’s safe to start without valve covers on for just 10 seconds to get balance rates
Yeah, I have ran mine without the covers. If you leave the lowers on there is very little mess if it's idling pretty smooth. Without the lower halves it can dump a lot of oil that you would just have to clean up.

I asked about the lines because if they had rust or crud in there that got pushed into the new injector it could cause one to stick open and show those high flow numbers and knock. I cleaned mine up and soaked them overnight in CLR while I had my covers off trying to find my leak but if I buy new injectors I will probably get new high pressure lines too.
 

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Discussion Starter · #18 ·
Yeah, I have ran mine without the covers. If you leave the lowers on there is very little mess if it's idling pretty smooth. Without the lower halves it can dump a lot of oil that you would just have to clean up.

I asked about the lines because if they had rust or crud in there that got pushed into the new injector it could cause one to stick open and show those high flow numbers and knock. I cleaned mine up and soaked them overnight in CLR while I had my covers off trying to find my leak but if I buy new injectors I will probably get new high pressure lines too.
mine runs like shit but valves arnt making too much noise ... so maybe I can run it without covers just to see if it transfers when I switch them
 

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Discussion Starter · #19 ·
Yeah, I have ran mine without the covers. If you leave the lowers on there is very little mess if it's idling pretty smooth. Without the lower halves it can dump a lot of oil that you would just have to clean up.

I asked about the lines because if they had rust or crud in there that got pushed into the new injector it could cause one to stick open and show those high flow numbers and knock. I cleaned mine up and soaked them overnight in CLR while I had my covers off trying to find my leak but if I buy new injectors I will probably get new high pressure lines too.
Do you think it could be bent pushrods ? What could cause bent pushrods
 

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Do you think it could be bent pushrods ? What could cause bent pushrods
I am not sure about whether bent push rods could cause this or not. Causes of that though could be many. I have seen them bend due to timing being wrong and the valves interfere with the piston and the push rod is often the weak link. I suppose there could be enough slack to let one fall out of the rocker's socket but you would have heard that terrible clatter for a while before it got that bad. I have also seen water in a cylinder do it because water won't compress like air and fuel does. I think that's the only causes for bending them I can think of off the top of my head.

I sheared a cam up front by the gear on a 5.9 cummins towing a load of cattle once. It instantly died but momentum bent most the push rods on the valves that were still open when the cam stopped turning and the crank kept going. At least your truck still runs so it's not that bad :D

My money is on injector #3 being bad.
 
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