I installed the egr blocker plate on my 09 lmm and now its making a wierd whistling noise and it de-rated the power. i know i have to retune the truck but im also having a hard time installing the fuel rail plug and suggestions or pics would be greatly appreciated.

 

For one man i wouldnt even begin to mod these 07.5 up trucks unless you have a tune ready to load to kill the regen and emissions codes.

Also dont mess with the FPRV unless you absolutley see you need to.( loosing rail pressure) This is a last resort in my book and i wish i never would have messed with mine.

 

Tim, would you please elaborate for me?

Just trying to learn what works, what doesn't, and why. Thanks!

 

The FPRV ( fuel pressure relieve valve) is on the end of the drivers side fuel rail.

Its' job is just as it named, to relieve too high a fuel pressure, but it can cause low rail pressure problems also.

It has a spring inside, every time it " pops" it gets weaker.

When you tune a Duramax or other common rail fuel injected diesel, you are commanding more fuel / psi than the the FPRV SOMETIMES Likes, it might pop on ya, causeing 0087 codes( low rail pressure).

So lots of guys including myself buy a Race Valve from PPE , its a glorified Plug. Has no parts inside/springs, just a plain old plug.

Now the bitch of this FPRV or Race Valve is the install, They are VERY VERY VERY VERY PICKY !!!! And the stock one is tight as ****, very hard to break loose and no damn room between engine and firewall. But it can be done as i and many others have.

Getting the new one tight is also tough. It is just a threaded machine fit with an O-ring.

Since the Duramax runs at 23,000 + fuel Psi, you can imagine how bad the fuel want to escape, If the plug doesnt seal correctly you wont hold commanded fuel pressure.

So this is why i say dont mess with the Fprv unless its absolutley needed.

I did mine cause all the cool kids were doing it, i should have waited to see if i really needed it. Now on my Race tune i pop 0087s from time to time and have for the last 2 -3 years, it just pissed me off so bad i quit trying to race my truck and got back in the gasser game.

My truck runs strong till about the 1/8 mile, then the 0087 code pops and my truck falls on its face, my best ET 3 years ago was a 13.6 . If i could get it to not pop the code it should be a solid 12.9 sec truck, as tons of others with the same combo as me run.


Just def. do a lift pump and exhaust, No egr for you i believe so no block plate needed, and of course EFI Live tuning and hold on to your hat! Intake is very necessary for the LB7 as the stock one is small, specially compared to the 06 up LBZ-LMM LML.

And run additive every tank, todays diesel is crap thanks to the govt. , No lubricity like the old stuff. Never use trans fluid in a common rail diesel for lube, 2 stroke oil / power service/ lucas fuel treatment is all good stuff and OK.

 

Yep, unless you are running a pretty stout tune, messing with the FPRV is usually unnecesary.

 

Yeah the FPRV is a pain in the *** to get to im just going to leave it in till i really need it.

 

my guess is the noise is a leak maybe you installed the blocker plate incorrectly and exhaust gass is leaking out..... but that shouldnt really cause a lack of power unless its a serious leak

did you get a blocker plug or shimms for the rail
if you need the shimms and or plug you must have a decent tune I needed shims when i stacked tuners, Im against the plug I think the shims a better idea, but if you needed to mess with the fuel rail you obviously have a tune requireing more fuel than the truck is built for so i would highly suggest a lift pump aswell!