Fuel Pressure and Boost Numbers
#1
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Fuel Pressure and Boost Numbers
I've had my truck about 3 weeks and I installed my gauges, BHAF, and Vulcan lp relocation kit last weekend. I was only able to drive it for a short time after the install, and then a few miles today, and now I have a couple of questions.
First, my lift pump was acting weird when I first moved it down to the frame. It initially ran 14psi at idle, and about 11 psi WOT, then when idling in the driveway the fp jumped down to 6psi. I could tap the throttle and the pressure would immediately jump back to 15psi. I could hear a different sound coming from the lp for the different pressures. It did this intermittantly that day. Then today it did it again when I first started the truck, but once I started driving the pressure didn't drop below 11psi agian. Should this be cause for concern???
Also, I was wondering about my boost pressure. I think I've read where I should get about 20 to 21 psi with my setup (no boost elbow or fooler). Well, I wasn't able to get more than 16psi today. I was running empty, but I did tackle a few nice hills. It would go to 16 fairly quickly, but never go higher. Is this normal??
Thanks in advance
Brad
First, my lift pump was acting weird when I first moved it down to the frame. It initially ran 14psi at idle, and about 11 psi WOT, then when idling in the driveway the fp jumped down to 6psi. I could tap the throttle and the pressure would immediately jump back to 15psi. I could hear a different sound coming from the lp for the different pressures. It did this intermittantly that day. Then today it did it again when I first started the truck, but once I started driving the pressure didn't drop below 11psi agian. Should this be cause for concern???
Also, I was wondering about my boost pressure. I think I've read where I should get about 20 to 21 psi with my setup (no boost elbow or fooler). Well, I wasn't able to get more than 16psi today. I was running empty, but I did tackle a few nice hills. It would go to 16 fairly quickly, but never go higher. Is this normal??
Thanks in advance
Brad
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I would watch and listen to the LP for awhile. It sounds like its starting to go... But It could be just a loose wire too. So double check all your work. Make sure you got a tight fit on the power connector.
As for boost it sound low. It can get 20 PSI in just about any gear. I would check your boots and your wastegate. The wastegate might be stuck partial open.
As for boost it sound low. It can get 20 PSI in just about any gear. I would check your boots and your wastegate. The wastegate might be stuck partial open.
#3
Re: Fuel Pressure and Boost Numbers
Originally posted by bamadzl
...my lift pump was acting weird when I first moved it down to the frame. It initially ran 14psi at idle, and about 11 psi WOT, then when idling in the driveway the fp jumped down to 6psi. I could tap the throttle and the pressure would immediately jump back to 15psi. I could hear a different sound coming from the lp for the different pressures. It did this intermittantly that day. Then today it did it again when I first started the truck, but once I started driving the pressure didn't drop below 11psi agian. Should this be cause for concern???
...my lift pump was acting weird when I first moved it down to the frame. It initially ran 14psi at idle, and about 11 psi WOT, then when idling in the driveway the fp jumped down to 6psi. I could tap the throttle and the pressure would immediately jump back to 15psi. I could hear a different sound coming from the lp for the different pressures. It did this intermittantly that day. Then today it did it again when I first started the truck, but once I started driving the pressure didn't drop below 11psi agian. Should this be cause for concern???
#4
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Yeah, coming in to work this morning it was jumping around a good bit. It never goes below 6 psi, but I would prefer a steady pressure. I think I'm going to try a Holley pump.
Any other thoughts on the boost numbers???
Brad
Any other thoughts on the boost numbers???
Brad
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Your boost depends on where you are taking the pressure reading. Should be around 20 to 21 at turbo and you will probally loose about 3 psi through the inter-cooler and intake, so about 17 or 18 at the manifold on stock truck. Plus your guage could be off by 1 or 2 psi.
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My boost gauge is connected to the 3/4" port on the block just behind the fuel filter housing. I did manage to get it up to 18 psi today. Is this correct for a stock truck with the gauge in this location??
Thanks
Brad
Thanks
Brad
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Yeah it's been super hot down here since my gauges have been installed.
How would I go about checking the wastegate? I don't even know where it is.
Brad
How would I go about checking the wastegate? I don't even know where it is.
Brad
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