Can you put a Peugeot 406 1.9 diesel engine in a Peugeot 806 1.9 diesel?

Yes, you can generally swap a Peugeot 406 1.9 diesel engine into a Peugeot 806 1.9 diesel, as they share similar engine designs and components. However, you must ensure that the engine mounts, transmission, and ECU compatibility are addressed. Additionally, modifications to the wiring harness and potentially the exhaust system might be necessary for a successful installation. Always consult with a professional mechanic for specific compatibility and installation details.