AdBlue reservoir
Stores the reducing-agent solution used by an SCR system.
In a dedicated body or underbody location on equipped diesel cars.
The system supplies correctly dosed solution through a delivery unit; it is separate from the fuel system.
A separate supply tank for exhaust cleanup.
Level or dosing warnings can involve fluid, heater, pump or sensing problems.
Condition, contamination, operating pattern and the underlying engine matter more than a universal age limit.
Sensors and joints differ greatly from complete after-treatment assemblies. First repair the cause of contamination or abnormal combustion.
AdBlue goes in its own BMW filler, never into the diesel fuel tank.
BMW diesel models fitted with a urea-dosing SCR system; not every BMW diesel uses this equipment.