C5 V6 petrol fuel pressure regulator upgrade

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Harlequin
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C5 V6 petrol fuel pressure regulator upgrade

Post by Harlequin » 31 Jul 2019, 20:44

Heya all, am looking to improve my V6 fuel pressure. Having changed the Xantia V6 to the bosch 3.5 bar one , its really is quite nippy now , i would like to do the same with the C5 V6

Citroen part number for the C5 V6 petrol is 1563G4 and Bosch number on mine ( as fitted) is 0280161511

so, which one would i be looking for as an upgrade?

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xantia_v6
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Re: C5 V6 petrol fuel pressure regulator upgrade

Post by xantia_v6 » 31 Jul 2019, 21:22

The C5 may still use the same regulator as the Xantia (I have not looked it up).

Be aware that if your C5 has a trip computer, it will under-read the fuel consumption and overestimate the range with the higher pressure regulator.

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Re: C5 V6 petrol fuel pressure regulator upgrade

Post by Harlequin » 01 Aug 2019, 16:29

Thank you - sadly they are different. On teh xantia its mounted under the forward fuel rail , whereas on my C5 its mounted off to the side . On the C5 it also doesnt have the vaccuum control pipe as well

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Re: C5 V6 petrol fuel pressure regulator upgrade

Post by xantia_v6 » 01 Aug 2019, 17:18

On the Xantia and probably the C5, there are 2 pressure regulators, one with the vacuum connection and one without. The one with the vacuum connection sets the rail pressure, the other is a pulse damper.

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Re: C5 V6 petrol fuel pressure regulator upgrade

Post by Harlequin » 01 Aug 2019, 18:13

Am looking on service citroen ; the xantia ones are on both fuel rails - fuel pressure on the front one and pulse dampener on the rear. The C5 is very different - the pulse dampener is on the fuel pipes before the fuel rail and i cant find the regulator on the diagrams at all!

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Re: C5 V6 petrol fuel pressure regulator upgrade

Post by Harlequin » 06 Aug 2019, 15:45

Ok so having pulled the inlet manifold to repalce a duff coil these are both ends of the fuel rail:

https://ibb.co/hmY5hvp
68252122-10162368846570556-4563468555193942016-n.jpg
and
67899729-10162368846515556-1728960117459648512-n.jpg
https://ibb.co/xzMq2HK
Last edited by myglaren on 06 Aug 2019, 16:18, edited 1 time in total.
Reason: Images added.

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Paul-R
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Re: C5 V6 petrol fuel pressure regulator upgrade

Post by Paul-R » 06 Aug 2019, 15:51

Image not showing for me. Instead of using a hosting service why not upload the image directly here?

Instructions how: viewtopic.php?f=13&t=56796

EDIT you've changed the post to give links. It would still be better to upload them here.
Last edited by Paul-R on 06 Aug 2019, 15:59, edited 2 times in total.

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Re: C5 V6 petrol fuel pressure regulator upgrade

Post by Harlequin » 06 Aug 2019, 15:53

Photobucket are paid accounts now - i changed the links, so maybe they are clickable?

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myglaren
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Re: C5 V6 petrol fuel pressure regulator upgrade

Post by myglaren » 06 Aug 2019, 16:19

Images edited in.

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Re: C5 V6 petrol fuel pressure regulator upgrade

Post by Harlequin » 21 Aug 2019, 17:04

Thank you, sadly still none the wiser, dont know where it is on an ES9A in my C5!

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GiveMeABreak
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Re: C5 V6 petrol fuel pressure regulator upgrade

Post by GiveMeABreak » 21 Aug 2019, 17:35

What's your VIN? - there are a few different EMS on these, I'll see what I have.

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Re: C5 V6 petrol fuel pressure regulator upgrade

Post by Harlequin » 21 Aug 2019, 17:37

VF7**************[VIN obfuscated, can be read by forum staff]

Thank you sir!

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Re: C5 V6 petrol fuel pressure regulator upgrade

Post by GiveMeABreak » 21 Aug 2019, 19:39

You're going to kick yourself - the reason you can't find it is because it's in the fuel tank! :rofl2:

Here's the components of the fuel system for reference (Bosch ME 7.4.7) It's item (9) on the diagram.
Click Image to Zoom
Harley A.PNG
(1) Fuel consumption data.
(2) Injection ignition test warning lamp.
(3) tachometer.
(4) Air conditioning ECU.
(5) multifunction screen.
(6) Built-in systems interface .
(7) Transponder .
(8) Automatic gearbox ECU .
(9) Pump, fuel filter and pressure regulator assembly (except grande exportation).
(10) Battery .
(11) pressostat.
(12) Engine speed sensor .
(13) The camshaft position sensor (x2).
(14) Motorised throttle housing .
(15) canister discharge electrovalve.
(16) electric cooling fan unit.
(17) Pencil type sparking plug (x6).
(18) Petrol injector (x6).
(19) Variable timing electrovalve (x2).
(20) Downstream oxygen sensor (x2).
(21) Upstream oxygen sensor (x2).
(22) Engine coolant temperature sensor .
(23) Knock sensor (x2).
(24) Power steering pressure sensor .
(25) Integral pressure sensor.
(26) Accelerator pedal position sensor.
(27) Air temperature sensor .
(28) Diagnostic connector .
(29) ignition injection control unit.
Harley B.PNG
(30) Pulsation damper.
(31) Spark plugs (x6).
(32) Fuel tank.
(33) Canister reservoir.
(34) Pressure relief valve.
(35) Exhaust system.

It's a combined Pump, Fuel Filter and Pressure Regulator Assembly, made by Marwall.

So it's submerged in the tank, operates on 12V, with a pressure of 3 Bars, has a Flow rate of 115 to 120 l/h and the regulation pressure is 3.5 bars.

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Re: C5 V6 petrol fuel pressure regulator upgrade

Post by GiveMeABreak » 21 Aug 2019, 19:40

^ Sorry about the delay - the Forum had an outage - just as I submitted my post!

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Re: C5 V6 petrol fuel pressure regulator upgrade

Post by Harlequin » 21 Aug 2019, 19:47

argh! so i literally cannot change it - its 3.5 bar already?

Thank you Marc!