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: Contact Authorized Mazda Dealer and Have Vehicle Inspected
If any of the following warning lights or the indicator light turns on/flashes, the system may have a malfunction. Contact an Authorized Mazda Dealer to have your vehicle inspected. ...

Mazda 6 Service Manual: Refrigerant lines removal/installation
1. Remove the battery. 2. Discharge the refrigerant from the system. (See RECOVERY.) (See CHARGING.) 3. Remove the washer tank. (L.H.D. only) (See WASHER TANK REMOVAL/INSTALLATION.) 4. Remove the air cleaner cover, air cleaner element and air cleaner case. (See INTAKE-AIR SYSTEM REMOVAL/INST ...