Mazda 6 Service Manual: No.7 slow return to idle

No.6 cranks normally but will not start

No.8 engine runs rough/rolling idle

Other materials:

Mazda 6 Service Manual: Gear Shift Indicator (GSI)
The Gear Shift Indicator (GSI) supports you to obtain optimum fuel economy and smooth driving. It displays the selected gear position in the instrument cluster as well as notifies the driver to change to the most suitable gear position corresponding to the actual driving condition. CAUTIO ...

Mazda 6 Service Manual: Plastic Part Maintenance
When cleaning the plastic lenses of the lights, do not use gasoline, kerosene, rectified spirit, paint, thinner, highly acidic detergents, or strongly alkaline detergents. Otherwise, these chemical agents can discolor or damage the surfaces resulting in a significant loss in functionalit ...