Injector Balance Rates 5.9

[ThatGuyDonk]

Hello all,

I did some searching and found little info on what all influences the Injector balance rates. I have an 06 3500 with a fresh rebuild. Cylinders 1 and 6 were fuel washed and needed to be worked. I had the head and block worked before i reassembled with new internals and all bosch factory rebuilt injectors. I have 3k on the build now and it still seems like something is wrong. Only aftermarket items are a sinister fuel filter, fuel rail return block off plug, ats 3000 turbo, intake and exhaust.

truck retorqe.hpl


Attached is a short drive logging commanded fuel pressure and desired fuel pressure as long as a period of idling before and after to view injector balance.
From what i see it is increasing fuel to cylinder number 6 to try and balance. It sits right at +4mm which by what i have found on here shows to be a dead injector. However it was replaced at the same time as the others, what other factors could I have in play? I re torqued the connecting tubes with no change. The only options i can think of at the moment is maybe that valve lash is set tight on that cylinder causing it to have lower compression, or maybe the injector really is just bad.

Any outside imput is welcom....

The truck used to have a smarty jr on it, so im locked from doing much with it until i have the computer re flashed to factory

[super_kev]

Rebuilt injectors are bad news on the forums; they are a hit and miss at times. I'd go with Big Bang as they've figured it out, or truly new (not reman) injectors.

[ThatGuyDonk]

Quick update, after removing and testing the injectors yet another time I found they were all within spec. I noticed I was also having other issues when driving, AC was cutting in and out frequently and the truck would run worse when the AC was on. I completely removed the engine harness and inspected it for any shorts or bare spots and did not find any defects. So I began chasing what I thought was a fuel issue and replaced the cp3, rail sensor, and in tank pump because of the fuel pressure fluctuations I was seeing when the truck would start to run rough. At that point all that was left was the computer, so I did some research and ordered a new ECM from All computer resources. The computer did not have any codes to begin with and showed zero physical indication it was faulty. However replacing it corrected my running issues and I now build and hold fuel pressure as intended and the truck drives as it should. It has been 1k issue free so I feel confident the issue is resolved.

[flubyux2]

hey, what did the injection shop actually have to say about the injectors?
i have a set of Torque diesel motorsport S1's in my truck with about 7000miles. they were reportedly tested and came back ok from TDM. however, my truck has a cold-start misfire accompanied by smoke but clears up after a few seconds.
i have finally gotten some data thanks to HPT and saw one injector was peaked out at +4mm. it comes down but still is high at idle. at cruise, they all get closer to 0.Xmm rates across the board. its just at low pulse/flow that my rates are off. Do you think im just being too picky? i know they wont be 0.0mm; thats just reality.