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Holden 5L Fuel Reg

HoldenSS5L

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Hi all,

Did a search but couldnt really find what I was looking for, am wondering if anyone knows where I can get the fuel pressure reg on the return to tank fuel line, want brand new to ensure I am not getting something that is no better then mine.

Also can someone explain to me how the fuel reg on the input side of the fuel rails works exactly, the one with a vacuum line running to it...

Thanks all

Shaun
 

Trevor loves holden.

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Same principle changing a V6 regulator, Repco or Autobarn should have them. The one on the passenger side is a non adjustable dampener to stop fuel hammer
 

HoldenSS5L

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Same principle changing a V6 regulator, Repco or Autobarn should have them. The one on the passenger side is a non adjustable dampener to stop fuel hammer
hmmmm...

So am I right in assuming that when there is no vacuum the reg closes off to a certain level or completely and then when there is vacuum is allows more fuel back to tank/rail pressure to back off ??

Shaun
 

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That's why its called a regulator once the pressure is right it allows the diaphragm to open allowing the unused fuel back to your tank, it also helps to start your car when been shut off for a while, fuel should remain it the rail once turned off, without the pressure the fuel cant be sprayed through the injectors, vacuum is to keep the fuel at a constant pressure at idle and so on as it open and closes once the spring reaches the pressure, if the diaphragm isn't sealing then that means no fuel pressure.
 
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mechanic

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How it works:
A fuel pressure reg is designed to maintain a pressure differential between the inside and the outside of the fuel injector pintle.

When the engine is idling, there is a high vacuum in the inlet manifold. This helps to suck fuel out of the injector.
When the engine is full-open throttle, there is no inlet manifold vacuum. Nothing to help suck out the fuel.
Early model ECU programming was not smart enough to compensate for this difference.

The regulator has a plunger valve connected to a diaphragm. When the vacuum is high (idle) the diaphragm is sucked back and the plunger opens the fuel line. Fuel is released back to the tank and fuel line pressure drops. At full-throttle the regulator diaphragm is released, the valve closes and fuel pressure rises to full.

Modern ECUs simply change fuel injection pulse-width to compensate for manifold vacuum, so have no need for manifold-controlled fuel pressure.
 

HoldenSS5L

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Awesome thanks for taking the time to right good quality replies they have been super helpful guys...

Shaun
 
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