Mazda 6 Service Manual: No.9 fast idle/runs on

No.8 engine runs rough/rolling idle

No.10 low idle/stalls during deceleration

Other materials:

Mazda 6 Service Manual: Distance Recognition Support System (DRSS) (Some models)
The Distance Recognition Support System (DRSS) measures the distance between your vehicle and a vehicle ahead using a radar sensor (front) while the vehicle speed is about 30 km/h (19 mph) or faster, and if your vehicle approaches a vehicle ahead more closely than what is appropriate for maint ...

Mazda 6 Service Manual: Recommendations for Shifting
Upshifting For normal acceleration and cruising, Mazda recommends these shift points: *1 Always observe local speed limit regulations. Downshifting When you must slow down in heavy traffic or on a steep upgrade, downshift before the engine starts to overwork. This gives better acceleration w ...