djjmorgan

My 2016 A5 2.0 Sportback (2007-2016 model) has developed an Adblue fault that reads “Adblue: system fault. No restart in 600 miles! See owner’s manual”. The adblue tank has been topped up to full (took approx 5 litres to fill to full) and I have driven the car a few times and added around 50 miles, to allow time for the adblue level sensor to reset. We also drained 0.5 litres of adblue in case I’d over filled it. My mates OBD reader shows error code P20E8, which when deleted, immediately returns. I tried disconnecting the adblue pipe in the engine bay, but noticed that after 2 mins 40 seconds, the flow of adblue stops. Approx 1 litre is pumped out before stopping. This was repeated twice, with the same result. I then tried the old Ctrl-alt-delete and disconnected the car battery for 20 minutes to allow the car to reset, deleting the fault before disconnecting. After 20 minutes, I then reconnected everything. The fault immediately returned. I then took the car for a 15 min drive to make sure the engine was hot. At the end, with the engine still running, I disconnected the adblue pipe in the engine bay and nothing was being pumped out. Is this right, or is it a failure of the adblue pump? I now have 550 miles to “No Restart”. 😱 Cheers!