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Discussion Starter · #1 ·
05 lly, 174k miles, k&n cold air intake, diablo predator, and just put in the ppe fprv shim (which fixed my previous problem). But now, If I'm stopped at a red light and I turn the radio down, I can hear it idling weird. It'll go upppp, then lowwwww, upppppp, then lowwwwww, and so. like it isn't a constant hum. Its more of an up and down kind of thing. any ideas?
 

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sounds kind of like a fpr (fuel pressure regulator) going out to me
 

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Discussion Starter · #4 ·
so how much will one of those cost me? And where is the best place to get one?
 

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Log it first. There are other reasons this happens. If your desired and actual pressure are in disparity, then replace it.
 

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Discussion Starter · #8 ·
Log it first. There are other reasons this happens. If your desired and actual pressure are in disparity, then replace it.

I'm not very mechanically inclined. What do you mean by "log it"?
 

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Discussion Starter · #10 ·
ttt

Is this 100% the fpr, or are there so other ideas I could check out first?

Because the truck accelerates and black smokes and does everything fine, but when it idles it just idles high...then low..high...then low
 

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Discussion Starter · #11 ·
a slow pulsing would be a good way to describe it
 

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Does it "surge" and not very noticeable on TAC or EGT? Thats what mine did. A new FPR fixed mine.
 

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X2 on that^^^^^^ Mine does the exact same thing.. I put 2 stroke oil and it kinda smooth's it out but not compleatly...
What was the mixture ratio you used for 2cycle to Diesel?:gearjamin
 

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Discussion Starter · #14 ·
Does it "surge" and not very noticeable on TAC or EGT? Thats what mine did. A new FPR fixed mine.

Alright thanks. Did you do it yourself, or take it to a dealer?
 

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My LLY used to do that too, I switched my additive to cheap walmart outboad oil instead. Its gone now. 200:1 ratio.
 
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