V50 Engine 2.0D : ECM-2002 / Particle Filter Pressure Sensor

[D5Pete]

Hello,
I'm trying to diagnose an ECM-2002 code which I found when scanning the car with VIDA following an oil change. VIDA's fault-finding advice for the code suggests testing the DPF differential pressure sensor at engine idle - it should give a reading of 3hPa to 20hPa. Mine returns 0hPa at idle, so it fails this test. However, the value does increase with engine revs.

I used VIDA to record RPM and sensor pressure for a quick test drive - see attachment. It seems like the sensor has a max delta pressure of about 155hPa amd it is responding to the transient flow in the DPF.

My question is: what is the failure mode for these sensors? Do they flat-out stop returning a signal, or is it a more gradual failure? I haven't experienced any symptoms such as limp mode yet but I want to get on top of this before it becomes a problem.

Another possibility of course is the piping between sensor and DPF - I haven't checked this yet.

Thanks in advance for any feedback on the above!

Car details:
V50 2004, D4204T (100kW), Euro 5

[iainmd]

Check the pipes before anything else. Ours was split for months at least without us noticing and no impact on performance.

[D5Pete]

Thanks, I'll check out the pipes then. Any area to concentrate on in particular? I see there are some rubber hoses which connect to aluminium pipes which I assume lead to the DPF. Will have to tear into it when the weather gets better...

[iainmd]

Yes, it's those two rubber hoses that run from midway up the DPF to the pressure sensor mounted beside the battery. Ours has rubbed through towards the bottom. They are better accessed from underneath with the undertray removed then you can easily get to them.

If that turns out to be your problem new hoses are about £50.

[D5Pete]

Great, thanks. At this age they probably need replacing - I might do so with silicone hoses instead of OEM rubber.