Ford Focus - Differential Pressure Values

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Wed 6 Jul 2016 21:01
Ford Focus - Differential Pressure Values - bigshorty40

Hi All

Quick query I need some advice on, hoping someone in the know might be able to help.

Can anyone please tell me what the ideal differential pressures are for a 2006 Ford Focus 1.6 TDCI 110bhp model (DV6 engine)? Values are measured in kPa.

Many thanks in advance.

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Thu 7 Jul 2016 15:22
Ford Focus - Differential Pressure Values - Peter D

differential pressures for what part of the car exactly. Regards Peter

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Thu 7 Jul 2016 16:38
Ford Focus - Differential Pressure Values - elekie&a/c doctor
I suspect we are talking dpf differential pressures?
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Thu 7 Jul 2016 16:43
Ford Focus - Differential Pressure Values - bigshorty40

Indeed it is the DPF differential pressures, how did you guess?

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Thu 7 Jul 2016 18:00
Ford Focus - Differential Pressure Values - Peter D

Have you seen all the DPF cleaning techniques on YouTube. Regards Peter

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Thu 7 Jul 2016 18:58
Ford Focus - Differential Pressure Values - bigshorty40

If you are referring to the cleaning techniques that involve washing out with power hose, yes I have seen them, but I don't really know how effective they are. Also, if the DPF has been cleaned, doesn't the PCM / ECU have to be reprogrammed / reset, as it will still be working based on the values / readings of the DPF as it is at the moment, before being cleaned? I've also heard it can be a bit risky cleaning with water as it can make the ash in the DPF set like concrete.

Thing is I can monitor the differential pressures of my DPF, I just don't know what sort of values I'm looking for them to be good readings.

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Thu 7 Jul 2016 19:45
Ford Focus - Differential Pressure Values - hardway

Doesn't your scan tool have a function for displaying DPF regen and a percentage for the DPF itself?

Your engine is a Peugeot and my PP diagnostics can.

So if the DPF reading is say 90% and a regen doesn't take the % down a significant amount then the DPF is beyond fixing.

Though I have heard good things about "Wurth" DPF cleaner,

Which actually gets sprayed into the post DPF pressure sensor hole.

But I'd still suggest further investigation,

it could be the DPF but it could be a pressure sensor.

Posting your DPF Mbar readings at idle and say 3000rpm might help.

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Thu 7 Jul 2016 20:11
Ford Focus - Differential Pressure Values - bigshorty40

I use Forscan which measures 'differential pressure on particulate filter' (DP_DPF) in kPa. To measure a regen I use a combination of EGT sensor readings (PPFT) and 'distance since last regeneration trial' (DIST_REGEN) which resets itself to 0.0km once a regen has been acheived. I did some live data scanning yesterday and was able to establish that the car is performing regens as should be.

I've heard that kPa readings for DP_DPF of <10kPa are normal readings, however the lower the better, however I've also seen info that says that <30kPa readings are considered normal. This has now left me confused as to what sort of readings I should be getting for a good DPF and bad one. From the live data scan yesterday I was able to see that at 1600rpm in 5th gear the DP_DPF reading was 2.5kPa, and when accelerating to 2350rpm in 5th gear the reading levelled off at 7.0kPa.

Not sure if any of this info is of use to any of you. Any views would be greatly appreciated.

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