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Discussion Starter #1
My LBZ has recently started to have a light haze smoke at idle. Aprroximately a year ago it started having a slightly different sound(tick) under power and at certain RPM's and fuel pressures. I noticed way back that when i would accelerate hard, it would throw a pulsating black smoke(Truck tune rarely ever throws smoke). Also, towing any kind of load the tick and noise is very loud(seems to be a loss of power as well when towing). Truck has 230K miles with original injectors.

Truck threw code P0087 Fuel Rail/System Pressure Too Low when it went into limp mode for the first time several months ago. When changing the oil, there is no metal shavings on the drain plug so I don't think it is anything mechanical. Truck has plenty of power and minimal noise when I'm not towing. Ticking/knocking is very prominent with any kind of load.

Balance rates in park are on left and drive on right:
1 -0.5, -0.2
2 1.9, 3.7
3 0.5, 0.7
4 -0.8, -1.8
5 0.1, -0.6
6 -0.4, -1.8
7 -0.7, -0.7
8 0.0, 0.8

Any ideas on this? Does this sound like injector problems?

Thanks
 

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The FPRV spring could be tired. Has the FPRV ever been shimmed? Balance rates are acceptable but keep an eye on #2. Anything over 4.0 and it's time to replace but one marginal injector won't throw a P0087 code.
 

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Discussion Starter #4
Do you ever use a fuel additive? If not try running some Diesel Kleen or whatever you prefer:

https://www.amazon.com/Power-Service-Diesel-Kleen-Additive/dp/B002NV4XXE/ref=sr_1_7?keywords=diesel+clean&qid=1581438589&sr=8-7

It might take a couple of tank fulls but this has helped me with similar symptoms.

As far as the P0087 do a search here and you will see that their are several potential failure points that can cause this. Do you have a lift pump?

Let us know what you find.

Cheers.
I do run additives. I run DK and Ive ran AMSOIL and Lucas before. No difference noticed in noise. NO lift pump installed
 

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Discussion Starter #5
The FPRV spring could be tired. Has the FPRV ever been shimmed? Balance rates are acceptable but keep an eye on #2. Anything over 4.0 and it's time to replace but one marginal injector won't throw a P0087 code.
FPRV hasnt been shimmed.
 

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Discussion Starter #6
I ordered the FPRV shim kit. Gone give that a try. Anybody else got any adice? I know that balance rates at idle are different than the rates under load or higher pressures. I heard that the Tech II can manipulate the injectors to find out under load. Should I take it to the dealer and try this?
 

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Throwing guesses at it.....
IMO, shim route in the end is a waste of time; 1, if the spring is weak, it's weak. Shim just delays the inevitable, or multiples just turn it into a rail plug with no travel. And in rare cases, even a plug can leak.

Bottle test, see if the FPRV is actually leaking by and returning fuel...verify it as a potential cause or part of the P0087 problem.

Injectors and fuel limps; balance rates won't tell ya a thing in that regard. You've got to measure fuel return, see if they're leaking off.

But there's 6 different things that can either be THE cause of the limp, or an accumulation of a little bit of all 6.
 

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MY '07 threw the dreaded P0087 code when I was towing our TT on a 106 degree summer day 5 years ago. Called Dustin at ATP, the solution that worked for me, shimmed the FPRV and added a lift pump. The problem hasn't returned...
 
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