P1457 Fault Code C5 1.6 Hdi 2006

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Stub Mandrel
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Joined: 19 May 2020, 16:48

P1457 Fault Code C5 1.6 Hdi 2006

Unread post by Stub Mandrel »

I'm getting the dreaded 'depollution system faulty' message from time to time, although the car is running well at the moment. The only issue is a smell of exhaust that builds up when stationary.

I've checked around the injectors and no signs of leaks/soot, in fact I can't find any sign of where the smell is coming from. I can't see/feel any hose leaks anywhere.

I read the fault codes and they were mostly repeats of 'less flow through ERG than expected' and 'Maff sensor not as expected' and 'unable to pull vacuum in tank'...

I've cleared the codes to see what comes up, but I didn't note the numbers...

Googling the unable to pull vacuum suggests that it's a lack of pressure difference across the DPF that could be a leaky sensor, leaky hose or even a cracked manifold or manifold gasket. The latter seems unlikely as the engine is quiet and there seems to be a good exhaust flow.

I suspect a small leak somewhere, is it possible/likely its some sort of hose fault upstream of the DFP pressure sensor as this could be more likely to show up as a fault with a small leak?

Any suggestions for fault finding?

I'll update if the codes reappear.