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: 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 ...

Mazda 6 Service Manual: Door switch removal/installation
Front 1. Disconnect the negative battery cable. 2. Remove in the order indicated in the table. 3. Install in the reverse order of removal. Rear 1. Disconnect the negative battery cable. 2. Remove in the order indicated in the table. 3. Install in the reverse order of removal. ...