C5 HDi Fuel Pressure Regulator Testing

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citronut
Posts: 10937
Joined: 29 Apr 2005, 00:46
Location: United Kingdom east sussex
My Cars:
x 92

Re: C5 HDi Fuel Pressure Regulator Testing

Post by citronut »

it should also be part of the chassis/VIN No. make up, if you still can find it send me the last 8 digits of you chassis/VIN No. and i can get it with that from service citroen
Regards, malcolm.

current ride a BX 1.7 TZD estate
1986 MK1 BX 1.9na D Auto(in Mothman Andy's stable )
layed up roppy 1.9TD XANT estate, now gone to meet her maker
purple and lilac metalic 2CV(VIOLET)registered to her in doors
1972 DS special been layed up aprox 31 years
BX
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Joined: 30 Oct 2009, 00:53
Location: Ireland
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x 17

Re: C5 HDi Fuel Pressure Regulator Testing

Post by BX »

Please excuse me if I have missed some important details as I skipped over the whole pantomime section of "he can", "oh no he can't".
You need to move away from the shot in the dark method of fault finding and approach things methodically. What you have told us is that the priming pump is ok. I assume that your car is Bosch equipped and that you mean the low pressure in-tank pump and that it is pumping good quantities of fuel through the fuel filter towards the high pressure pump. Have you checked that the immobiliser is disarming. If it is plug in a diagnostic tester. Check the current fault codes and note them then clear them. Codes have their place but the presence of a code does not necessarily mean you have to change a component. Likewise absence of a code does not mean there is no fault. View the live data. Check the cranking rpm. This lets you know if the crankshaft sensor is working. It will also let you know if the starter is cranking quickly enough. Check the fuel rail pressure. If there isn't sufficient pressure injection will not be initiated by the ECU. If there is no pressure showing at all the next check is to see if the high pressure pump is actually pumping. Do this by loosening the high pressure pipe. Assuming the pump is pumping and that the regulator is ok the next check is to do a leak off test on the injector.
xantom
Posts: 65
Joined: 26 Aug 2008, 14:33
Location: Near Lincoln
My Cars: Renault 16 - my first car bought secondhand in 1980. Lasted a couple of months before dreadful rust brought it to an end.
Renault 18 estate petrol. Bought in 1981. only new car I've ever owned and only because it was tax free to Forces in Germany. Lasted 18 months before accident write off.
Renault 18 saloon petrol. bought in 1988. lasted 3 years before accident and repair cost ended it.
Xantia Esate TD. Bought in 2006. First Citroen and bought because of the suspension and potential to run on veg oil. Apart from a stint owning a doomed C5 estate I've owned nothing but Xantia TD saloons and estates since. All have Bosch pumps so veg oil since 2006 for me.
x 3

Re: C5 HDi Fuel Pressure Regulator Testing

Post by xantom »

Sorry to have been so long about completing this. I apologise because I get a little irritated if something interesting to me just withers away. Anyway, I solved the problem after a while away from the car for unrelated reasons. Having removed both the Crankshaft and Camshaft sensors, checked them as much as I could off the car, and then replaced them to no effect I gritted my teeth and set about the fuel tank. I drained it of the 60 odd litres of 70:30 diesel to fresh veggie oil mix and removed the fuel level sensor and pump unit. The pump seemed lively enough on a direct feed of 12 volts from a battery so I replaced the unit, added 10 ltrs of diesel and cranked her up. Took less than 15 secs of cranking to recharge the fuel lines etc before she fired and ran perfectly. I'm convinced now that the veggie oil proportion was to blame because she's happy as a happy thing now. I do suspect that the in-tank pump is performing badly, well enough to push diesel but not enough oomph to push diesel even slightly thickened by a proportion of veggie. I'm not inclined to experiment now either, not now that she's running but later this summer I might treat myself to a new in-tank pump and try out a little veggie at a time..... maybe. Thanks all for your ideas. Tom
Tom
1998 Xantia Mk2 1.9TD Saloon
1996 Xantia 1.9TD Estate Mk1
(Previously Old Guy's)
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