What is this?

SAT999

SAT999

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What is this? Fuel pressure regulator? Is it disassembled, regulated?
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The pressure after the fuel pump must be 48 psi. Does this mean that the rail pressure drops from this regulator to some limits and the rail pressure must be, for example, 40 psi? What would happen if this regulator did not work properly?
 
Yes. That's why there is a fuel valve regulator. And if high pressure reaches the rail, there is no other regulator to lower it? IIRC is not regulator, only pulse damper? Or if from the pump and its valve to the rail the pressure is lower or higher than necessary, there is nothing to help the system?
 
It's a fuel rail damper, has nothing to do with pressure or returning fuel to the tank via a non existant return line.

As per description and operation of the factory service manual:
The fuel damper is used only to help control fuel pressure pulsations. These pulsations are the result of the firing of the fuel injectors. It is not used as a fuel pressure regulator.
 
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I will measure the pressure of the fuel system. I am trying to find out if this pressure, which I will measure before the rail, is the final pressure that reaches the injectors. If there is incorrect pressure, I will replace the pump and its valve.
 
mrblaine said:
Regardless of what that is called or what it does, there is only one line that carries fuel from the tank to the fuel rail. It is a returnless system.
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Yep, the pressure regulator is located in the top of the fuel pump module. There is no return line from the rail to the tank.
SAT999 said:
I will measure the pressure of the fuel system. I am trying to find out if this pressure, which I will measure before the rail, is the final pressure that reaches the injectors. If there is incorrect pressure, I will replace the pump and its valve.
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The pressure at the rail is equal to the pressure at the pump, unless you have a damaged fuel line or something. I would also recommend driving the vehicle with the pressure gauge hooked up. I usually tape it to the windshield and drive around the block. Not all fuel pressure issues will show up at idle or even a throttle snap. Sometimes you need good solid load to see a pressure drop.
 
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SAT999 said:
Low or high pressure would cause the exhaust to explode when the throttle is back?
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When driving if the throttle is closed the fuel injectors should be cut off, so pressure would have no relivance in that situation unless there is a problem.
 
SAT999 said:
Unless a lot of fuel has leaked before closing the throttle?
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It would have to be a ton. The engine will clear the manifold with quickness at cruise RPM. Maybe a leaking injector or possibly an exhaust leak. Both could cause decel misfires.
 
I'm not sure what the fuel pressure should be for a 2002-2004 Wrangler 2.4L engine. In one place it says 48 psi, in another place for 2001-2006 Chrysler and Dodge it says 53 psi to 60 psi.
 
There are members parting out TJs of various years in the Jeep Wrangler TJ Classifieds on this forum in the Parts For Sale.
Contact one of them to see if they have what you need.
 
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