C5 2008 (X7 ?) Turbo Fault

[GiveMeABreak]

Sorry, I've been a little busy - he has an X7 Mike:

C5 (X7) 4 DOOR SALOON 1.6 HDi 110 particle emission filter (DV6TED4) Manual gearbox 5

Turbo Air Piping	Air Filter Hoses

1434C8 is the highlighted Part 14 - the sleeve on the piping after the MAF

[MikeT]

Yep, pretty much same layout as my engine, Marc
If #14 is leaking, the turbo will be sucking air that's unmetered by the MAF.

[GiveMeABreak]

And here are the turbo air union pipes - is this what you were looking for?

[MikeT]

Admiral probably asked for those as I mentioned them being a possible cause of his issue but I'm 99% sure he's ID'd the issue with part#14 being broken. Shame the mechanics didn't check it as they did say "low pressure" on the turbo inlet side - which I now take to mean low MAF reading.

ETA: That's also likely to have caused regeneration failure too and the risk of dpf clogging warning.

[admiral51]

Thanks Marc,Mike
I was looking at the right parts just did not realise
I have put the sleeve back in, reason i noticed it was because oil ( not a lot ) has been dripping from it, j clip was and is still tight but guess oil is from EGR system.
I need to pay more attention to the car, do not drive it very often so could have been dripping for a while as i guess they did not remove the pipe
Not slating them, i asked for diag without proper equipment so stopped them as soon as they said TURBO lol
Going to order the sleeve regardless, not going to fit it until i have had a diag session, even i can change that part in under 4 hrs
Marc thankyou for the parts picture have now checked prices and all turbo vac lines and the sleeve come to about £140 , though if you could check it for me much appreciated.
Mike i have sent you a pm, and thank you for all your input and help so far, them beer tokens are coming your way

[GiveMeABreak]

Which numbers on the diagrams do you want prices checked?

[admiral51]

Marc i am thinking 6/7/8 are the pipes that go to the vacuum actuator ?
Just looking at what i can change for not too much outlay, the sleeve insert that you identified as #14 i think is just under £19 inc vat much cheaper than a turbo

[MikeT]

Thanks Marc,Mike
I was looking at the right parts just did not realise
I have put the sleeve back in, reason i noticed it was because oil ( not a lot ) has been dripping from it,

Maybe mechanic was there then, oil and excess play in the shaft are two signs of turbo failure

[MikeT]

Sorry admiral, I think my PM's gone rogue on me. Can't reply to you anymore for some reason. I wrote a wordy response and clicked send but on checking today, can't see it anywhere.
Tried replying again but the system won't let me. Tried starting a new PM thread and again, after clicking send, it's nowhere to be seen

[GiveMeABreak]

Mike - please check back in the other thread about the PM situation - I have updated my response.

[admiral51]

Got it thanks Mike have replied

[admiral51]

Great to see Mike T again today, helpful as always and a whizz with his Diagbox.
I finally replaced the sleeve insert before i took the car over to see Mike and to be honest it drove an awful lot better than before, £20 well spent.
Mike cleared all previous faults, there were quite a few i must admit but Mike is better placed to explain them
I now only have 1 fault ( changed the sidelight bulb Mike ) but still have the Service light on and the DPF warning but i can live with that as the DPF has been regening and levels are fine.
There is an issue with the Turbo data, IIRC the ECU was asking for 2200 milli bar of boost but only got 1850 @ 2500 rpm.
Thanks to Mikes knowledge he checked the Turbo Actuator and although it works the travel of the arm seems to be compromised, it appears that it is not returning to its closed position.
Checking on Mikes car ( same engine ) the travel is greater and cannot be manually pushed back up, where as on mine the arm can be moved up and then drops a few mm.
Could this part be at fault?
The Turbo is boosting but if the starting position is incorrect it cannot give full boost as the travel of the arm is too short?
I have looked on tinter web and the actuator is available as a stand alone part Turbo Actuator but guess there are some available in the UK.
Much happier today now i have some answers, again a big thanks to Mike T for his time and patience.
All thoughts and comments will be greatly appreciated, i really want to keep this car on the road

[MikeT]

Was good to see you too mate though neither myself or my netbook were performing optimally so not sure you got the best use out of us. Though I think we did gain some useful info along the way.

You've pretty much summed it up as I understand it. After clearing historical faults and ignoring Multiscreen/Radio/Glowplug faults, we were left with failed sidelight & turbo pressure fault of which you say you've since fixed the former, leaving us with...

P0299: Turbo pressure electrovalve control
Characterisation: Flow too low
Status: Permanent

Variables associated with the fault
Engine speed: 2570 rpm
Turbo pressure: 1729 mBar
Turbo pressure reference value: 2200 mBar
Turbo electrovalve open cycle ratio: 49%
Output injected: 44 mg/stroke

Having had time to review the information, it's even more annoying the live parameter data was lagging so much. It's much better using Lexia but wasn't given that option with your car.
As such, I'd like to offer you another session using my main laptop as it's more powerful. There are graphed discrepancies recorded between referenced and sensed values that I can't trust due to the lag.

What we do now know is that regenerations are occuring regularly and soot loading at the time was shown to be 18%, having covered over 300km since the last regen.
So what does the warning risk of filter clogging really mean in this context? I'm afraid I have no solid answer for that and can only hope that fixing the turbo pressure fault will resolve it.

Although the fault code snapshot shows the turbo underboosting, Diagbox had in fact recorded peak pressure over 2.2 Bar several times during the drive so I don't know what to make of that either as I've still to discover the particulars of the variable vane control according to other engine variables. ie degree of closing/opening vs engine load, air flow, rpm etc.

We do know that the actuator arms moves down when the engine is started, which is to be expected. As mentioned, there are further tests detailed by Citroen for checking correct vaccuum pressures at specified engine rpm and I recommend having those checked.
In hindsight, I wouldn't read much into the mystery of the arm's reluctance to fully spring back compared to mine at this point, despite my intial comments. Please don't order a new one on that basis, tempting as it may seem. Maybe my car is the odd one out as I have nothing else to compare. I'd really like to see more accurate live data asap.

[admiral51]

Thanks Mike for everything and posting the above, as in other posts i had to go and see another C5 today for my lad, so now we have 2 C5's and a C4 in the family lol
The fact that the Turbo is boosting to 2.2 Bar at times and not at other times seems a little bit odd, yes more live data could help but my thinking is that the Turbo is not totally at fault, yes it is 10 yrs old but something somewhere is stopping it giving the boost when needed.
The other thing that we both forgot to mention is that the fault has been present for over 15k miles( data from Diag ) but the DPF and service warning has been present for less than 1 k miles, and the DPF has been regenning within those 1 k miles with the warning on.
Sticking actuator arm, possible, cheap ish replacement, but my thoughts keep going back to the fact that i can plant my foot and get nothing, but lift of for a split second and plant foot and full beans.
May need someone else to drive it to get that feeling ??
Yes it needs a full oil/fuel/air filter change, not been done for 2 years but will that change anything??
In my head i have this feeling that the DPF and Service light is not related to the issue,how to turn it off is another subject, but something somewhere is not playing ball.
I understand what Mike is saying, but if the actuator is sticky, for the price of the part is it worth trying it, it is a blinking lot less expense than a Turbo lol
Looking at the removal/replacement i think it can be done without removal of the Turbo and need for gaskets but can anyone point me in the right direction for gaskets just in case

Colin

[MikeT]

Perhaps Marc would be kind enough to provide VIN-specific information from Citroen; Fault code descriptions and testing procedures for instance?

Timely servicing is important due to fine tolerances of modern engines. For instance, what effect do you think a blocked air, fuel or oil filter might have on turbo boost?