I have a recurring issue where the voltage for the DPF pressure sensor drops causing incorrect soot values and restricted performance.

I know the fault lies either direct on the ECM connection or the immediate wiring in the plug as if I lift the harness or press the connectors the voltage shoots up to normal, when driving if the nose is pointing downhill or I’m going over bumps it will drop and eventually throw RP

Also I parked the car on the drive and got the voltage to flatline and checked from the sensor up to the ecm, there was no change until fiddling in the ecm area when it came back to life.

Live data when loose leading to RP (see drops)



Live data after pushing in ECM connectors (working perfect)



I’m at my wits end … I’ve removed the plug and checked for damaged pins and all is ok and there’s no obvious bulging or splits. I’ve fully reseated the plug and ensured it’s connected it’s stabilised for now but I don’t have much confidence.

Does anyone know what wire(s) or pin(s) relates directly to the dpf pressure sensor as it would help me pinpoint the issue further and hopefully get a final fix?

I’ve dug through the WM and found a wiring diagram,