According to Peugeot, the use of sequential twin parallel turbochargers is a world first on a 4cylinder diesel car. The system (patented with Honeywell Turbo Technology) consists of two identical, small-diameter turbochargers.
At low engine speeds, a single turbocharger ensures engine responsiveness. It is then supported by a second turbocharger, which starts to operate in parallel between 2600 and 3200 rpm according to the applied load and atmospheric conditions. The entire range of engine speeds is therefore covered. The system is controlled entirely by the engine's electronic control unit (ECU). In addition, the low inertia and small size of the turbochargers reduce response time and improve throttle response.