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Discussion Starter · #1 ·
Hi , I've noticed people posting there fuel rail pressure being around 26,000 psi
I monitored mine at WOT and I only see 21-22,000 psi

Any suggestions on wat to do or test to fix this
I recently did the ported fuel rail fitting on the driver side and before I did that I was only seeing 19,000 psi

Thanks
 

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That's about normal. The LLY's didn't produce 26k like the 06+ trucks did. Think its around 23K.
 

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Discussion Starter · #3 ·
O, ok. Is there a way I can increase it , will it only go to 23k or if I do that ppe FPRV will it go higher ?
 

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You can install a LBZ fpr in your CP3. But you'll need EFI tunes to run it
 

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O, ok. Is there a way I can increase it , will it only go to 23k or if I do that ppe FPRV will it go higher ?
why increase it? If your getting the demanded fuel rail poressure of the lly, you can make plenty of power. 500-600hp easily with supporting mods
 

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Discussion Starter · #6 ·
I'm planing on getting EFI live tuneing soon
 

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The max on a LLY is 23k, as noted by Robby05.

But the LLY has a known weak FPRV- and some just shim the spring, [recommended], or some install a "Plug" available from many of the Forum Supporting Vendors. [Also known as a Race Valve]
 

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The max on a LLY is 23k, as noted by Robby05.

But the LLY has a known weak FPRV- and some just shim the spring, [recommended], or some install a "Plug" available from many of the Forum Supporting Vendors. [Also known as a Race Valve]
I have had my race valve in my glove box for months, one of these days I will install it. What is involved with shimming the spring?
 

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You just remove the valve-- dissamble ir-- install 2 #4 flat washers. Some vendors have the shim kit. $15-? Biggest problem is many are not careful and loose a part in the valve-- then it doesn't run. Pacific Performance Engineering - Diesel Specialists

I saved this when I shimmed my FPRV--
Removing the glow plug controller bracket was the hard part-- I even removed the turbo heat shield for room moved the return line a little so the flex socket would get in a little easier--

To remove the FPRV-- I ground one side off the 18 mm wrench so it would fit flush with the FPRV head, and then used another big wrench on the end of the 18 mm for additional leverage. It came right off-- It is important you have good contact on the head, because the head is shallow-- not full depth like a regular bolt. If you use a junk wrench, you may strip the head and it will be impossible to remove.

I got the washer from the local hardware store-- I believe it is stainless #4 size - .325 od and .028 thick. Cost 19 cents. They did not have the 20mm nut so I just chucked the pressure end of the FPRV in a vice -- attached a pair of vice grips to the head (hex side) and tapped the vice grips with a hammer- came right apart. Remove the spring and drop the washer inside the body- insert the spring and cap-- press together in a vice-- use cardboard or aluminum on the seat side, and stake the side to hold it together.

Be sure you protect the pressure side-(opposite side of the head) that seals against the seat in the fuel rail-- any damage to it, and it will not build pressure.

The install of the bracket is a little hard also-- I said FU, and cut the upper bracket from the engine mount part-- welded a tab and and now bolt it together-- now the upper glow module bracket is removable from the engine bracket-- works for me.

Do not loose the needle pin, spring, or the stock washer. If you do not put it back together the correct way-- the truck is DOA.
 

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What does the plug do that replaces the fuel sensor? I saw one on the dmax store but wasn't sure what its for? Does it fully replace the sensor as a delete or something?
 

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It is not a "Sensor"-- it is a "Release valve" When the pressure in the rail exceeds the holding pressure of the FICM spring-- it release some fuel rail pressure. [ex.-it may bleed off pressure at 18k-not 23k]

The "Plug" is just a solid part that blocks any release of the fuel rail pressure.
 

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I guess I'd have to see it.
 

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You just remove the valve-- dissamble ir-- install 2 #4 flat washers. Some vendors have the shim kit. $15-? Biggest problem is many are not careful and loose a part in the valve-- then it doesn't run. Pacific Performance Engineering - Diesel Specialists

I saved this when I shimmed my FPRV--
Removing the glow plug controller bracket was the hard part-- I even removed the turbo heat shield for room moved the return line a little so the flex socket would get in a little easier--

To remove the FPRV-- I ground one side off the 18 mm wrench so it would fit flush with the FPRV head, and then used another big wrench on the end of the 18 mm for additional leverage. It came right off-- It is important you have good contact on the head, because the head is shallow-- not full depth like a regular bolt. If you use a junk wrench, you may strip the head and it will be impossible to remove.

I got the washer from the local hardware store-- I believe it is stainless #4 size - .325 od and .028 thick. Cost 19 cents. They did not have the 20mm nut so I just chucked the pressure end of the FPRV in a vice -- attached a pair of vice grips to the head (hex side) and tapped the vice grips with a hammer- came right apart. Remove the spring and drop the washer inside the body- insert the spring and cap-- press together in a vice-- use cardboard or aluminum on the seat side, and stake the side to hold it together.

Be sure you protect the pressure side-(opposite side of the head) that seals against the seat in the fuel rail-- any damage to it, and it will not build pressure.

The install of the bracket is a little hard also-- I said FU, and cut the upper bracket from the engine mount part-- welded a tab and and now bolt it together-- now the upper glow module bracket is removable from the engine bracket-- works for me.

Do not loose the needle pin, spring, or the stock washer. If you do not put it back together the correct way-- the truck is DOA.
thanks for the post, i will roll with the race valve first before I attemt to take this ^^
 
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