Fuel Pressure Funk - Competition Diesel.Com

AKDieseL · 01-27-2019, 12:03 AM

Last July I installed a new VP, new overflow valve, ISSPRO mechanical fuel pressure gauge with a snubber, aftermarket filter mount with a Cat 1R-0749 fuel filter, sump kit and a Raptor 150. I have maybe 20-30 hours on this system. Had several problems in the beginning, but they more or less stabilized, unfortunately by setting my pressure at 11psi. Low, but being that the truck is near stock, and the pressure held even on heavy acceleration, I dealt with it. Yesterday, I dug the truck out of the snow bank since we had a good 3 days of 30+ degree weather. After a spell on the charger to recuperate from Alaska winter, fired up just fine, albeit the pump took its sweet time to get up to pressure. (Pump runs on key power, no starter bump required). After she spent the night in the warm shop so I could inspect the rear end, I fired her up, and pulled her outside to play with the pressure adjuster. It took over 1 full turn to go from 11 psi to 13 psi. Didn't seem right to me. Driving around the block, it held decent pressure, but the ups and downs I did see seemed rather sluggish. Can anybody offer me any insight? Plan on calling outflow soon as I am able. Thank you.

SixOhh · 01-28-2019, 11:59 PM

I had the same issue with my 2nd gen.

I moved the sensor to the air dog and I lowered my pressure to 10 psi to stabilise it.

On another note, the cold really affects how diesel flows. Even down here in TX on an 80* day I can have my air dog at set at 10 psi and its smooth on the gauge . Then I can start the truck in west Texas in 25-30* weather and see the gauge rocking between 15-18 psi... even on a warm motor and brand new filters.

I have a vp pump from blue chip diesel and he has explained to me that the vp also has an internal bypass iirc

AKDieseL · 01-29-2019, 02:29 PM

Yesterday was a fun filled adventure, but it gained results. By my third call into Pureflow, they realized they were giving me info and troubleshooting on the wrong pump. It was getting old hearing how my regulator should have 3 o-rings, when there wasn't a groove or boss or anything for more than 2. Also, yes, there was supposed to be a ball in there. Emphasis on "supposed to be". After pulling the pump off the truck to really be able to look in the regulator port, dropping tiny non-magnetic parts in the snow, trying to find them before the falling snow covered them forever, and soaking myself in diesel, Pureflow is sending me a new ball, and hopefully wen it arrives it will solve my problems.

I do wish that i would have gone with an electronic gauge with a sending unit as opposed to a mechanical, but alas, i did not, and this will have to suffice for now.

If anyone has any know how on exactly the order of parts for the regulator, i sure could use the info. i believe the order is as follows:

Pump Base
First Spring (Stiffer)
Small Plunger
Collar looking thing
Ball
Second Spring (Softer)
Then Adjuster Assembly

If someone can confirm or correct me, please do. thank you.

01-27-2019, 12:03 AM	#1
AKDieseL Name: AKDieseL Title: Rookie Status: Not Here Join Date: Jan 2018 Location: Talkeetna, Alaska Member`s Gallery Posts: 29	Fuel Pressure Funk Last July I installed a new VP, new overflow valve, ISSPRO mechanical fuel pressure gauge with a snubber, aftermarket filter mount with a Cat 1R-0749 fuel filter, sump kit and a Raptor 150. I have maybe 20-30 hours on this system. Had several problems in the beginning, but they more or less stabilized, unfortunately by setting my pressure at 11psi. Low, but being that the truck is near stock, and the pressure held even on heavy acceleration, I dealt with it. Yesterday, I dug the truck out of the snow bank since we had a good 3 days of 30+ degree weather. After a spell on the charger to recuperate from Alaska winter, fired up just fine, albeit the pump took its sweet time to get up to pressure. (Pump runs on key power, no starter bump required). After she spent the night in the warm shop so I could inspect the rear end, I fired her up, and pulled her outside to play with the pressure adjuster. It took over 1 full turn to go from 11 psi to 13 psi. Didn't seem right to me. Driving around the block, it held decent pressure, but the ups and downs I did see seemed rather sluggish. Can anybody offer me any insight? Plan on calling outflow soon as I am able. Thank you.

01-28-2019, 11:59 PM	#2
SixOhh Name: SixOhh Title: EPA unfriendly Status: Not Here Join Date: Aug 2008 Location: Magnolia, TX Member`s Gallery Posts: 1,108	I had the same issue with my 2nd gen. I moved the sensor to the air dog and I lowered my pressure to 10 psi to stabilise it. On another note, the cold really affects how diesel flows. Even down here in TX on an 80* day I can have my air dog at set at 10 psi and its smooth on the gauge . Then I can start the truck in west Texas in 25-30* weather and see the gauge rocking between 15-18 psi... even on a warm motor and brand new filters. I have a vp pump from blue chip diesel and he has explained to me that the vp also has an internal bypass iirc __________________ 07' Silver 2500 5.9 4x4 LWB Goerend 48re-csp5/EFI- T&C Mild Cp3-F1 Apex 7.5 -S369sxe Amsoil Coolant Bypass -Airdog-D&J- Hamilton 188/220 -AFE-ARP Opti-Lube H-Town Off-Road

01-29-2019, 02:29 PM	#3
AKDieseL Name: AKDieseL Title: Rookie Status: Not Here Join Date: Jan 2018 Location: Talkeetna, Alaska Member`s Gallery Posts: 29	Yesterday was a fun filled adventure, but it gained results. By my third call into Pureflow, they realized they were giving me info and troubleshooting on the wrong pump. It was getting old hearing how my regulator should have 3 o-rings, when there wasn't a groove or boss or anything for more than 2. Also, yes, there was supposed to be a ball in there. Emphasis on "supposed to be". After pulling the pump off the truck to really be able to look in the regulator port, dropping tiny non-magnetic parts in the snow, trying to find them before the falling snow covered them forever, and soaking myself in diesel, Pureflow is sending me a new ball, and hopefully wen it arrives it will solve my problems. I do wish that i would have gone with an electronic gauge with a sending unit as opposed to a mechanical, but alas, i did not, and this will have to suffice for now. If anyone has any know how on exactly the order of parts for the regulator, i sure could use the info. i believe the order is as follows: Pump Base First Spring (Stiffer) Small Plunger Collar looking thing Ball Second Spring (Softer) Then Adjuster Assembly If someone can confirm or correct me, please do. thank you.