Thanks for your reply. The car has 114000 on the clock. DDE means digital diesel elecrtronics. I looked it up and this is what I got:-
The world’s first electronic diesel management system revolutionizes engine technology.
In 1987 BMW became the first carmaker in the world to introduce Digital Diesel Electronics (DDE) in the 324td. This all-electronic digital engine management control revolutionized the ongoing development of diesel technology, the innovations we see today such as turbulence chamber, pre-chamber or direct-injection technology all being based on this bold step into the future. At the same time DDE was an important prerequisite for introducing electronically controlled automatic transmission and driving stability systems in the diesel. Electronic management controls both emissions and fuel consumption, engine noise and motoring refinement far more precisely and quickly than a mechanical system. Taking numerous parameters into account, therefore, DDE was able for the first time, using map control, to inject exactly the right amount of fuel at the right time as a function of operating requirements. And to this very day, the high standard of accuracy ensured by DDE throughout the entire running life of the engine remains an important prerequisite for maintaining emission standards now becoming increasingly stringent the world over.
Thanks for your reply