Ad Blue EML fault

[johnmi]

Hi All

i must have bought a A7 that has every fault.

The Nox sensor was replaced two years ago and now the EmL has come on again but this time for a fault in the Ad Blue system .

Audi garage could not find the cause but the only way was to have two hours of diagnostics to then advise I needed a new Ad Blue thank that has cost me £2400.

They claim not seen this before on my 3.0 TDi .

Has anybody experienced this and whilst it’s now 6 years old only covered 35.5k miles. I’m going to raise it with Audi.

John M