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New injectors now knocks at idle

1612 Views 8 Replies 3 Participants Last post by  dhillman111
I just put swamps stage 2 split shot injectors now it knocks at an idle. the reason I put new injectors in is because it was burning oil #8 o-ring was bad. I made sure they were completely seated and torqued to 120 inch pounds. I made sure the seats were clean and vacuumed out the cylinders. I still have to send my chip in to get re-flashed could that cause the knock? the truck has 234,410 miles on it thanks in advance
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Definitely need to be running the right tunes. Check your fuel pressure as well.

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swamps says these injectors will work with the factory ford programming. fuel pressure is around 60 psi
What did they change in the injectors? Bigger nozzle?

Stage 2 splits are very oil hungry.

Keep in mind it takes 100 miles of driving to get air out.
I'm not sure what they change in the injectors they say they don't need any other mods
That doesn't mean you have 60 psi.

sorry I should have mentioned I'm new to this forum I should have said I have a fuel pressure, hpop, boost, egt,and trans temp gauge in the cab
Yea they are split shots like the factory injectors.

Those injectors you bought probably have a larger 30% over nozzle.

With the proper programming changes you would see a power increase.

But the stock calibration still only injects 135cc and it does not adjust for a larger nozzle.

So I will gain zero power until you electronically adjust for these changes.

Have you checked fuel pressure at idle and under load?

What is Icp and duty cycle as well?

The number 8 injector gets oil and fuel starved. Modded splits are even more oil hungry.
fuel pressure was around 60psi I didn't watch it that close under load ill have to check it tomorrow. the knock is louder when I put it in gear and have my foot on the brake compared to just idling in park. what should the Icp duty cycle be?I haven't checked that yet. what are my options to feed #8 the fuel and oil it needs?
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