My 2007 Mazda5 2.0D Sport is failing the emissions test for it's MOT to pass.
After the initail failure I had the DPF deep cleaned which improved the smoke test readings on restest including it's general performance yet it still failed the emissions test.
I subsequently took it to a diesel specialist who performed the emissions test and yet again... it failed!
I am advised that oil is getting into the system and contributing to the high readings... From where though?
The thing is that MOT regulations have changed recently and my car would have more than likely passed the emissions test prior to the changes.

Any ideas?

Thanks in advance.