[Beard]

Hello.
wrote you correctly (aspy39) - (Node)
remove the inlet tube, blow through it and the fitting that holds it, also blow it out. remove the backpressure sensor and blow it out too. values (minus) should not be. If that doesn't help, then just replace the sensor.
If I'm not mistaken at idle, the maximum allowable back pressure should be + 35mbr.
at 2000 rpm - not higher than +70mbr.
at 4000 rpm - no more than +200 mbr.
Negative values should not be!
your particulate filter is fine. (according to your testimony)

sorry, in your car the back pressure tube is non-removable.
it still needs to be cleaned and blown out.

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