Stage 1 logic widens the 1.6 HDI’s usable torque band while retaining factory-smooth manners. EGR flow and its diagnostics are fully disabled, keeping the intake charge clean. Torque, boost and smoke limiters are rescaled with balanced air–fuel targets so the five-speed gearbox remains within OEM load margins. Cold-start, idle and part-throttle areas are refined to preserve stock fuel economy on cruise, yet deliver a crisper pedal feel in city traffic.