Is a Audi a6 quattro 1998 2.8 engine interchangeable with a Audi a6 2001 quattro 2.8 engine?

The 1998 Audi A6 Quattro 2.8 engine is not directly interchangeable with the 2001 Audi A6 Quattro 2.8 engine due to differences in engine management systems, wiring harnesses, and other components that evolved between those model years. Additionally, changes in emissions standards and technology may affect compatibility. While some parts may be similar or usable with modifications, a complete engine swap would likely require extensive adjustments and may not be advisable without professional guidance.