Fuel rail pressure

2004LB7

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Quite a few have replaced them with regular bolts so they are less likely to strip out the next time they need to remove them. The Allen key hex bolts style can fill with dirt and grime. This makes it easy to strip it out if the key doesn't sit down all the way. Pain in the butt when it happens
 

BM06lbz

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Feb 11, 2026
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Hey, just a question I have. So being that there was metal shavings in my fuel filter. I decided to change my CP3 as well as my injectors. Instead of spending grand on new one, my cousin just let me have his used one that was sitting in his garage. It was working when he took it off. I’m guessing he just upgraded for more power. My question is if he pulled it off and then let it set for a while. Is there any chance that rust could develop inside? I hooked up a fuel line to it, and spun the gear with my hand and flushed fuel through it and it looked fine and there was no rust flakes or anything.
I’m sure it’s just fine and I’ll probably just slap it on, but I also want to be careful with my new injectors
 

BM06lbz

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Feb 11, 2026
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Well it’s been sitting for at least over a year or longer maybe over 2
And there wasn’t fuel in it when I got it but once I got fuel running through it, it seems like it turned pretty good
 

BM06lbz

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Feb 11, 2026
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Hey, just checking before I get my injectors in, I can reuse the stock hold down bolts, correct? And also do I need to lube the bolts before I put them in or do I just put them in and torque them to spec
 

2004LB7

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Hey, just checking before I get my injectors in, I can reuse the stock hold down bolts, correct? And also do I need to lube the bolts before I put them in or do I just put them in and torque them to spec
You can, but it is advised to replace them. They sometimes stretch enough that the clamping force drops low enough that it can leak combustion gas. If they have already been reused once before, consider replacing them

Torque specs are without lube. I wouldn't have any issues lubing them as long as you account for that. If you can torque by feel, then lube shouldn't make a difference. If you need a torque wrench, then install dry
 

BM06lbz

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Feb 11, 2026
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Got them ordered, worth doing it right the first time I guess. also, I have a question on Torqing the lower valve cover bolts. I should be able to get most of them torqued with a torque wrench, but there’s two against the firewall on the driver side that I’m not sure I’ll be able to get. Is it fine to just guess as close as you possibly can. or is there other options?
 

2004LB7

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Got them ordered, worth doing it right the first time I guess. also, I have a question on Torqing the lower valve cover bolts. I should be able to get most of them torqued with a torque wrench, but there’s two against the firewall on the driver side that I’m not sure I’ll be able to get. Is it fine to just guess as close as you possibly can. or is there other options?
That's how I did it. Actually do it by feel on all of those. So probably cheating
 

Bdsankey

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If they're OEM output injectors, they need to be recoded correctly. If they're oversized, I have always put the same code in for all of them.

The ECM uses these codes to help account for the difference in output that each injector has.
 

Bdsankey

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I guess they would be oversized OEM?
If they're OEM output injectors, they need to be recoded correctly. If they're oversized, I have always put the same code in for all of them.

The ECM uses these codes to help account for the difference in output that each injector has.
See the above in bold from my reply but I would personally put the same injector code in for all of them.

OEM output means just that, OEM output. If they are any larger than stock then I use the above rule of thumb, it does not in any way at all matter what they started as or who built them.
 

Bdsankey

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OK, thanks yeah, I have an autel so I don’t think it should be too hard and I’m assuming injector to cylinder placement doesn’t matter
Not really. I personally always match them to the cylinder meaning #1 on the flowsheet goes in cyl 1, #2 on the sheet goes to cyl 2, #3 goes to cyl 3 and so on.

Another thing I've done on other platforms, mainly Cummins, is put the highest flowing injectors in the middle cylinders and the lowest flowing in the furthest out cylinders to help account for the minor airflow differences cylinders 1 & 6 see compared to 2/3/4/5.
 

2004LB7

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Not really. I personally always match them to the cylinder meaning #1 on the flowsheet goes in cyl 1, #2 on the sheet goes to cyl 2, #3 goes to cyl 3 and so on.

Another thing I've done on other platforms, mainly Cummins, is put the highest flowing injectors in the middle cylinders and the lowest flowing in the furthest out cylinders to help account for the minor airflow differences cylinders 1 & 6 see compared to 2/3/4/5.
Would it make sense to do a compression test and put the highest flowing in the lowest compression and lowest flowing in the highest compression so the power per cylinder is roughly evened out? Smother idle and less balance rate deviation?