C8 2.2HDi 170 Codes P1351 and P1447

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Peter Morgan
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Joined: 05 Dec 2019, 18:37

C8 2.2HDi 170 Codes P1351 and P1447

Post by Peter Morgan »

Hi All,

Looking for some suggestions before the trusty C8 gets towed away

As with many, long history of 'depollution fault' messages with the car. The second dpf was fitted at 160K miles as Citroen main dealer said dpf was more than 50% full and would need replacing soon anyway. Fault continued together with P0299 (pressure/air problem, I seem to recall). So, 2 new turbo sensors were fitted and this got rid of that code. However, antipollution fault message continued and car in limp mode. Dealer has now said that dpf is fine and there must be an 'electrical problem' and suspect that the ECU needs changing. Apparently uneconomic and in fact they were unable to source one.

Also changed in recent months - fuel filter

The P1351 code also exists - glowplugs? - but I believe that's quite common and there are no starting issues.

Can anyone suggest a work-round or further possible courses of action. The dealer suggested that a specialist could trick the ECU to ignore dpf messages - could this work. They said they couldn't (as a main dealer) have that done for me, but I may be able to find someone willing to do

Any words of wisdom gratefully received. Other than this, the car would continue for many more miles, I think

TIA

Peter

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GiveMeABreak
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Re: C8 2.2HDi 170 Codes P1351 and P1447

Post by GiveMeABreak »

The glow plugs are not only used for assisted starting in cold weather, they are also used by the engine ECU in assisted regeneration to help raise the temperature more rapidly, along with the operation of consumer electrical devices such as the heated rear windscreen for example. There are generally 2 errors - one where the relay is at fault and one where one or more glow plugs are not operating. So yes, they are not really required for starting in an HDi engine, but do have other uses.

What other fault codes have you now got coming up apart from the P1351? There should be another fault code stored if the engine ECU deems it necessary to put the engine into a back up mode.

Peter Morgan
Posts: 15
Joined: 05 Dec 2019, 18:37

Re: C8 2.2HDi 170 Codes P1351 and P1447

Post by Peter Morgan »

Hi Marc - Thanks for your response - sorry, per the heading, p1447

Best regards

Peter

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GiveMeABreak
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Re: C8 2.2HDi 170 Codes P1351 and P1447

Post by GiveMeABreak »

Sorry - couldn't see the wood for the trees.

P1447: Differential exhaust pressure signal: Clogged particle filter. Ok, so this fault is telling you that the difference in pressure entering and leaving the particle filter means that it is getting clogged or is blocked.

So the question is how many miles has the vehicle done? The particle filter may be at end of life - so may need a deep clean.

Has the vehicle been getting a good run lately?

Until resolved though, I would not drive the vehicle unnecessarily as if it is indeed getting blocked it is going to prohibit engine performance to the point the engine will start cutting out if it gets too bad.

Normally the regeneration should take care of the soot - but over time the ash and Cerine particles which cannot be burnt off will clog the filter. It is this that ultimately requires a deep clean or replacement of the particle filter.

Peter Morgan
Posts: 15
Joined: 05 Dec 2019, 18:37

Re: C8 2.2HDi 170 Codes P1351 and P1447

Post by Peter Morgan »

Marc, the dealership fitted a new dpf - but say the ECU won't recognise it as such and they cannot get the message to disappear or the car out of 'limp' mode (EML on too). They also found a split intercooler to turbo pipe which apparently is not available (so it has been taped up), I have no idea why it split as it is split on top, not underneath
Thanks for your help

Peter