fuel pressure
#1
08-04-2010 | 06:41 PM
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fuel pressure
I have a 2000 dodge ram 3500 diesel,i have a fuel guage on .
when i start truck it has 10-12 psi at idle
when driving with a load on ,have 3000 lb camper on back
it drops between 4 and 7 psi , when get up to 55 mph to 65 mph will go up to between 6 to 8 psi, is this pressure ok , or do i need to look at replacing lift pump
when i start truck it has 10-12 psi at idle
when driving with a load on ,have 3000 lb camper on back
it drops between 4 and 7 psi , when get up to 55 mph to 65 mph will go up to between 6 to 8 psi, is this pressure ok , or do i need to look at replacing lift pump
#3
08-17-2010 | 06:00 PM
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#5
08-18-2010 | 09:25 AM
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From: East Alabama
For both the CP3 and VP44, you want the pressure between 10 and 20 psi.
Ideally between 13 - 17 psi.
17 psi at idle and no lower than 13 psi at WOT will keep your injection pump happy.
Pressure below 7 psi on the VP44 is not what you want to see. The VP44, unlike the CP3, cannot draw it's own fuel and NEEDS good pressure. The fuel is it's cooling and lubrication.
The CP3 has it's own internal lift pump and is capable of drawing it's own fuel, but initially needs the pressure for starting, otherwise hard starts can occur. The CP3 needs volume more than it needs pressure.
Ideally between 13 - 17 psi.
17 psi at idle and no lower than 13 psi at WOT will keep your injection pump happy.
Pressure below 7 psi on the VP44 is not what you want to see. The VP44, unlike the CP3, cannot draw it's own fuel and NEEDS good pressure. The fuel is it's cooling and lubrication.
The CP3 has it's own internal lift pump and is capable of drawing it's own fuel, but initially needs the pressure for starting, otherwise hard starts can occur. The CP3 needs volume more than it needs pressure.
#6
08-19-2010 | 11:00 AM
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From: Omaha, NE
#7
08-22-2010 | 02:41 PM
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From: East Alabama
As long as the CP3 has any pressure at all, it's okay.
The CP3 has it's own internal lift pump that pulls it's own fuel, so the pressure isn't as critical.
It's not ideal, nor will it make full power with upgrades, but you're not going to damage it.
The VP44 in the 24V trucks needs the pressure. When the VP's pressure gets down into that 5-7 psi range, that's when you want to upgrade the pump.
You're fine though......although 13 - 17 psi is where you ideally want the pressure to be.
The CP3 has it's own internal lift pump that pulls it's own fuel, so the pressure isn't as critical.
It's not ideal, nor will it make full power with upgrades, but you're not going to damage it.
The VP44 in the 24V trucks needs the pressure. When the VP's pressure gets down into that 5-7 psi range, that's when you want to upgrade the pump.
You're fine though......although 13 - 17 psi is where you ideally want the pressure to be.