C5 1.6 HDI cutting out. Stranded in Cornwall!

[rogerfry1]

Hi Group.
I previously posted under "C5 De-pollution faulty warning after difficult starting" and had some useful comments. This problem (fuel starvation from air block) was solved but now I have a new one - which could be related. Previously, each time once the air block had passed through and the car started there were no further problems until the air got in again due to faulty connector, and with that fixed I had done 800 trouble free miles - until suddenly the engine management unit started shutting the engine off altogether but then allowed a restart straightaway.

I had one occurrence in London but then nothing for 200 miles coming on holiday. Thought it was a one-off until it started cutting out every few miles, and the last 70 of the journey were a nightmare with stops every few miles, so I'm effectively stranded in south Cornwall (near Fowey).

Symptoms are:
No discernible consistent conditions for cut out: engine can be cold or warm, any revs from idle to 3k, rain or dry. Suspicion that going up a steep hill in lower gear is more likely to make it happen but this may be a coincidence.
Completely clean cut out, as though ignition switched off. Depollution system faulty flag comes up, but everyone agrees this is very generic.
Once car has come to a complete stop engine will restart fairly easily, no coughing, although for around 4 seconds of cranking it doesn't fire, then suddenly does.
The NavDrive display is also cutting out and instantly restarting at different times.This may also be a coincidence as it used to do that occasionally towards the end of a long drive before any of the other problems started. But now it is doing it all the time.

I've seen a suggestion that it could be worth checking fuses for signs of burning. Any other ideas? I know I have to get the error code checked but reluctant to go to main dealer down here as it could be big money only to fix the wrong thing.

I'd be grateful for any advice.

[Northern_Mike]

Can you see the Lexia owners map? Is there one near you?

Sent from my GT-I9300 using Tapatalk

[SaabC5]

Roger have you ever had the DPF off the car. Having tried to start a car with a blocked DPF it sounds very similar to your problem, long time cranking, runs for a while and then dies. Its possible to split it, jet wash it out and then allow to dry before putting back on car.

[RichardW]

DPF blockage should ( ) bring up a specific message to that effect... When was the fuel filter last changed? I'd try that if you are able - shouldn't be too hard on a C5 which has access to the top of the engine. Failing that you will need Lexia, but my gues is you will find the error code is "Fuel pressure regulation: Leak" or similar. If not the fuel filter, then could be the pressure regulator. Or the pump. Or. Or.

Join the AA / RAC now, and then when it's time to go home, get a ride

[Peter.N.]

My 2.0. C5 was doing the same and strangely enough it happened in St Austell, I found it to be due to low oil level - not very low but enough for it to shut the engine down, once stopped the oil level would come up and it would start again.

Peter

[rogerfry1]

Thanks for all replies so far. Nearest Lexia on map is over 60 miles. I'll have to go to a nearer main dealer. The fuel filter was changed 800 miles ago. If the DPF was blocked wouldn't it go into Limp Home mode? Anyway, it isn't a case of long time cranking ever. It feels like something is simply tripping in the electrics.
Peter: checked oil and OK. That would have been a really easy one!

[Stickyfinger]

Mine did that exact same thing, cutting out dead with DePol/ASR...ect faults....frightening once just over the crest of a hill !.

It was the electrical plug (dpf) down behind the engine, a real swine to get to.

I cleaned it with contact cleaner and then it has been fine since.

[rogerfry1]

Thanks once again. I took it to Citroen St Austell for diagnostics. By then the fault was getting really bad and any hill was a nightmare. Very helpful and experienced mechanic. Dozens of fault codes but the main one was Fuel High pressure regulation rail pressure below ... Which means any time the engine is under load the problem occurs - not just hills. Because it could be any one of many components, all of which expensive, and because the fault has obviously developed from the previous leak fault I am tempted to accept that the cost of repair is likely to be greater than the car's value, and give up!

[Peter.N.]

If it has the same HP pump as the 2.0. 8 valve Hdi the pressure regulators themselves fail, I got a secondhand one off ebay for not to much money.

Peter

[isisalar]

This might be the cheapest way to get you home, taxed and tested and very simple. It's the second listing so could probably get the price down a bit. Might need to get that doseur valve sorted though.
http://www.ebay.co.uk/itm/Xantia-Estate ... SS:GB:3160" onclick="window.open(this.href);return false;
Cheers
Paul