Issues with FRP Spike

I have been having issues with my Fuel Rail Pressure dropping to 0 and back to desired. it does not always drop to 0 but it falls off, and i get a fuel knock. I have been running the same tune for almost 8 months now and problem just started 3 months ago. Here are some logs to see if anyone can help. I do not think its tune related but as tuners here i might get some insight on my issues.

I have upgraded my CP3 from stock to fleece power flow 750, changed fuel filters, changed fuel rail pressure sensor and went back to a stock tune. Still nothing not sure what else to check. I am running a Fass 220 and 100 hp injectors.

Any help would be very nice i am loosing it with this issue its driving me nuts.

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check the duty cycle of the fca, possible the fca is not working right.

Can you change to a good know pressure relief valve? Sounds like it's opening, releasing pressure and reseating.

Put a pressure gauge on the fuel filter side. If you see it spike, you are having a rail pop off issue.

Yea i am logging a few more things for adam to check thats what i was thinking as well but its a different fca on the new cp3 and im having the same issues as the old one so 2 bad fca thats crazy but i guess possible

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Originally Posted by Justin Time

Can you change to a good know pressure relief valve? Sounds like it's opening, releasing pressure and reseating.

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I have a plug in mine still from my last tuning session

Quote:

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Originally Posted by Turbo_Mike

Put a pressure gauge on the fuel filter side. If you see it spike, you are having a rail pop off issue.

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ok when i go back on days off i will give this a shot

Looking at your cruise control log, the pressure is extremely erratic and is overshooting then missing under.

You most certainly cant run a stock tune with an upgraded pump. The duty cycle and FCA response are incorrect.

I've seen this with DMAX guys putting a LBZ pump on a LB7 truck. The FCA response is incorrect and creates the pressure surge.

Quote:

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Originally Posted by Turbo_Mike

Looking at your cruise control log, the pressure is extremely erratic and is overshooting then missing under.

You most certainly cant run a stock tune with an upgraded pump. The duty cycle and FCA response are incorrect.

I've seen this with DMAX guys putting a LBZ pump on a LB7 truck. The FCA response is incorrect and creates the pressure surge.

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Sorry havent been on lately. What am i looking at i need to change? i will pull up my tune now that i have some time and look through it.

Quote:

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Originally Posted by Turbo_Mike

Looking at your cruise control log, the pressure is extremely erratic and is overshooting then missing under.

You most certainly cant run a stock tune with an upgraded pump. The duty cycle and FCA response are incorrect.

I've seen this with DMAX guys putting a LBZ pump on a LB7 truck. The FCA response is incorrect and creates the pressure surge.

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Also the upgraded pump came after the issues i started having them before i thought my cp3 was failing so i upgraded. everything that was mentioned i have done since the problem started.

So upon getting fed up with it i took the truck in to get a diag ran. Found out my injectors are going bad... less then 2 years and maybe 20k on them fucking industrial injection got some S&S in route this week!