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C34 Fuel Setup

Captain Wow

By Captain Wow,
in Four Door Family & Wagoneers

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Captain Wow Enthusiast

Captain Wow

Posted
Posted

Hey guy.

Was looking at my recently purchased C34 yesterday and noticed what I thought was a funny setup with the fuel hoses. In the engine bay it goes from hard line to soft line, then to the Tomi fuel reg then to the fuel rail. Then what I assumed was the return line to the tank, coming out of near the firewall, was the fuel filter. Do the rb25det neos run like this or has an idiot assembled it wrong?

My guess is the latter as it doesn't appear to make sense otherwise.

Cheers,

- Lance

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KiwiRS4T Grand Master

KiwiRS4T

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On the S1 ( I still have stock set-up) the fuel system goes like this:

The hard pipe goes to a fuel filter mounted in the engine bay near the RH strut tower and a rubber hose goes to the back (firewall) end of the fuel rail. There is a fuel regulator (still using the stocker) at the front end of the fuel rail and a rubber hose goes from there to a damper mounted just behind the filter and the return goes from there to the tank.

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Captain Wow Enthusiast

Captain Wow

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Okay thanks for that.

Mine isn't standard so it's hard for me to tell how it's meant to be. Does the fuel go in from the front or rear of the fuel rail? At the moment mine goes from the hard line, to a rubber line into the filter, then through the Tomei fuel pressure regulator (mounted on the drivers side strut tower) via rubber line into the front of the fuel rail. Then a rubber pipe comes off the back of the rail to the hard return line.

- Lance

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KiwiRS4T Grand Master

KiwiRS4T

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Posted

Okay thanks for that.

Mine isn't standard so it's hard for me to tell how it's meant to be. Does the fuel go in from the front or rear of the fuel rail? At the moment mine goes from the hard line, to a rubber line into the filter, then through the Tomei fuel pressure regulator (mounted on the drivers side strut tower) via rubber line into the front of the fuel rail. Then a rubber pipe comes off the back of the rail to the hard return line.

- Lance

No the regulator is at the end of the rail thus pressurising the rail. Its possible yours is plumbed wrongly. Have you pulled off a hose and turned on the pump to confirm where the fuel is coming from? Maybe you are returning fuel via the filter! Does your car run properly??!

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Captain Wow Enthusiast

Captain Wow

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I've re done it all last night. The car was surprisingly running well even with the fuel filter on the return line, and backwards. Now I've got it going from the hard line, to rubber through the filter, into the back of the fuel rail. From the fuel rail to rubber to the reg, then rubber down to the hard return. Sound alright?

Cheers,

- Lance

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