A few months my car had the "emissions update". When the VW garage completed this update the EGR failed and as a "goodwill gesture" they replaced the EGR. Fuel composition has been significantly reduced, with frequent regen.

I began smelling a strong acrid smell in the car, enough to burn my eyes and back of throat. I returned it to the VW garage and they agree about the fumes, and they also found the coolant to be black with what appears to be soot. They do not know the cause, although they seem to know it is unrelated to their previous work. They have sent the coolant fluid away for analysis.

I cannot help feel it is related to their emissions update and EGR work.

Any thoughts? Would really appreciate any information/ advice/ experiences.