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When i set my truck to 1100rpm high idle i get a skip in the motor.

tried doing a cylinder cutout and when cutting out engine it runs on each cylinder and while cutting out 1 cyl at a time it seems to make the same difference in the motor for all 6

ran injector perf. test and it fails injector 3 on test point 1 and injector 6 on test point 3

any ideas? both bad? injectors have about 200k miles on them replaced all 6 when overhaul was done.

fuel pressure leakdown test yields about 500psi of loss over several minutes and pump has been rebuilt before and due for another rebuild soon.

No one with any words of wisdom?

only thing i can think of is maybe ...
1100 is right where the engine transitions from idle injection timing into injection timing that is made for a load on the engine. you might just be teetering back and fourth between the 2 states and noticing the change is all. It likely will not hurt a thing if all else checks out ok.

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Do the cutout test at 1100 rpm

I did test at 1100. I've also had this happen once or twice at 900 rpm low idle. But does it every time at 1100 but the idle thing might be right as when you move it to 1050 or 1150 it goes away.

Just bothers me truck has a shake at idle where my dad's 2350 is smooth grant he has stock idle rpm I have mine at 725.