Mazda 6 Service Manual: No.4 hard to start/long crank/erratic start/erratic crank

No.3 will not crank

No.5 engine stalls-after start/at idle

Other materials:

Mazda 6 Service Manual: Drive Selection (Some models)
Drive selection is a system to switch the vehicle's drive mode. When the sport mode is selected, vehicle's response against accelerator operation is enhanced. This provides additional quick acceleration which may be needed to safely make maneuvers such as lane changes, merging onto freeways, o ...

Mazda 6 Service Manual: Dsc system inspection
Preparation 1. Verify that the battery is fully charged. 2. With ignition switch on, verify that the ABS warning light goes out after 2.4 seconds. 3. Turn the ignition switch off. 4. On level ground, jack up the vehicle and support it evenly on safety stands. 5. Shift the transaxle to N posi ...