Citroen C5 MkIII (X7) Engine Died Won't Start

[Steve Buck]

After a trip around Norwich southern bypass I pulled off onto a minor road and my suddenly lost all power - the engine died as I accelerated away from a roundabout and the car ground to a halt. I managed to bump start the car coasting down a hill, although the engine ran really rough and eventually died again. I was able to re-start the engine by turning the ignition with the accelerator flat to the floor and keeping the revs up, but it ran really rough and eventually died again. I was able to re-start and repeat this process and limp the last couple of miles home.

The car is a 2009 C5 MkIII (X7) 2.0 HDI 16V VTR+NAV (90k miles on the clock). The car cut out about 6 months previously with depolution, ASR/ESP and low oil pressure warnings - was able to re-start and continue OK. Have subsequently had a few depolution and ASR/ESP warnings but have generally ignored these as they seem to resolve themselves when the car is res-started next. Have also had some slight hesitation/flat spot when accelerating from low speed which I think May be EGR related, but I'm not sure whether a stuck EGR would cause the engine to die and not be able to re-started (the car won't start at all now).

My neighbour plugged his OBD II diagnostic reader in and the faults read were P0101 (MAF) and B13 (?). The MAF looks clean but could still be faulty I suppose. The EGR could be stuck, but would this cause the engine to die and not to start? I may try a blanking plate to eliminate the EGR possibility - any thoughts on any long term adverse effects on the engine/turbo? The other possibilities are the fuse box (original) which seem to be problematic on earlier cars (mine's Sept 2009 so not sure if it would be affected or not). Other possibilities could crankshaft/camshaft sensors.....

Any ideas what the problem is most likely to be? I may try blanking the EGR to perhaps eliminate that first, but am inclined to think it may be a faulty fuse box or possibly the MAF. Are there any tests that I could carry out or do I need a proper Lexia diagnostic carried out - is there someone knowledgable locally (Norwich/Norfolk) who has the equipment to read the codes?

Any thoughts on how to resuscitate my dead C5 would be greatly appreciated.

Thanks

[falling-out-with-my-car]

Try a diesel fuel filter first if the old one is over a year old it probably wants replacing soon they are cheap to.after that if it still won't start check the earth leads from the battery to body and gearbox if they are loose it can be the reason for total los of power to the electrics on a diesel car. My son had this problem a loose negative lead. Equally check the security of the positive lead. Citroen are renowned for skimping on the length of earth leads.

[Stickyfinger]

OBD readers lie about Citroen's and most PSA Cars......to read these you need the Lexia system.
There is a Lexia Map p[ost on the FAQ's

Why would you think its a EGR problem ?....btw its a lot more work than just a blanking plate on its own its own will throw engine management faults and limp home mode. If this has been advised as a possible cure for your problem, I personally would question the knowledge of the giver....sorry if that was rude.
Please take care of the electrics on these cars if your/someone is plugging things in, they like most cars these days can have very self destructive ECU's etc when they get shorted out /unplugged whist live etc

Others way way better at diagnostic questioning will I am sure chime in.

[vborovic]

Have subsequently had a few depolution and ASR/ESP warnings but have generally ignored these as they seem to resolve themselves when the car is res-started next

Don't want to make it sound like I'm rubbing it in, but this is your first issue right there, among others ... you just can't afford to ignore something the car shows, especially on these new ones ... a lot of things don't get displayed to the driver, which build up in the "shadows", but once you actually get some information, it might be too late (or to expensive). Generic OBDII readers are usually of little help, could point you in some direction, but you won't know whether the entire picture was shown to you ... Lexia/DiagBox is the only proper tool to actually get the PSA car to cooperate with you.

As for the EGR blanking, you know that this is against the laws and regulations? You should focus on fixing it, not avoiding it (if possible, both technically and financially).

I don't think both MAF & EGR would totally disable the engine from at least turning on an ignition attempt. The fuel filter could be the first checkpoint though.

[falling-out-with-my-car]

Err not exactly true for older cars like a mk1 or S2 xantia first registered before 1998 and not. Fitted with a catalytic converter. Exhaust gas reburn can be blanked off but I suspect this is not the problem in this case. It does sound like an electrical fault or fuelling problem to completely loose power as described. especially with the description saying that foot flat on the floor to get any power from the engine. To hazzard a guess I suspect at 90k the fuel tank filter could also do with a clean. It could also be air in the fuel line. Which can be a reason for.a diesel cutting out of this kind of mileage. I did hear something about the later cars having an electric fuel pump. I wonder if this is the problem? I am sure someone will be along soon to explore this possibility.

[vborovic]

Err not exactly true for older cars like a mk1 or S2 xantia first registered before 1998 and not.

We're talking about the car that was made in 2008, not those a decade ago ... ... things have obviously changed (and became more complicated than ever) ..

[vborovic]

I'll see if I can get some backed up info on this situation, vaguely remembering, the EGR itself shouldn't be a MOT, but it will usually cause an increase in the smoke test parameters ... if the car was on the border of passing before, after the EGR gets blanked out, it might possibly fail the smoke test ... so, basically you shot yourself in the foot by doing so ...

[RichardW]

It's not the EGR valve or the MAF stopping it. My first port of call would be the fuse box and / or the wiring loom to it - although a blocked diesel filter is also a candidate, but I wouldn't have expected this to just stop it without prior warning, and then not allow a re-start. If you can get it on Diagbox it will indicate what the ECU etc is and isn't seeing which may help pin it down. Fuseboxes for early cars are expensive unfortunately - if you post up the VIN, we can get a part no / price. Late ones are much cheaper, but I've not yet heard convincing evidence that you can fit one without problem.

[Gibbo2286]

I'm surprised no one has mentioned the in tank low pressure fuel pump. Too much reliance on Lexia and codes maybe.

[SaabC5]

Do you do lots of short stop/start cycles in your car. Depollution warning may mean a blocked DPF, if you've ignored the warning for months it could have got the point where its totally blocked and not allowing the exhaust gasses to escape, this will manifest itself as a car that won't run properly.

[Stickyfinger]

I'm surprised no one has mentioned the in tank low pressure fuel pump. Too much reliance on Lexia and codes maybe.

You just did....

[vborovic]

I'm surprised no one has mentioned the in tank low pressure fuel pump. Too much reliance on Lexia and codes maybe.

At this stage, it could pretty much be anything that we think would prevent the engine from starting, couldn't it? At least it is cheaper and faster to get the car diagnosed, compared to randomly testing each potential part for failure ... unless you're really lucky and hit the bad on on the first attempt ...

[RichardW]

It hasn't got a low P pump.....

[DickieG]

Blanking off or disconnecting the EGR valve on a car made much after 2005 will almost certainly result in the ECU going into limp home mode as the ECU will detect the lack of gas flow, in fact one possibility is that the EGR valve is blocked already or close to it at that mileage, remove and clean the valve and pipes running to/from the valve (I did one on a Fiat on Sunday). A very good place to start is a Lexia session and check the level of Eolys in the tank by looking at the translucent white section on the side of the tank, if it has run out of Eolys then that will cause similar problems, likewise if the DPF is blocked so a possible chicken and egg situation with emission equipment.

[Stickyfinger]

But all of the above would throw permanent faults and warnings wouldn't they ??