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: Oil cooler flushing
Note The contaminated cooler line (oil pipes and hoses) and auxiliary cooler must be flushed completely when ATX is overhauled or replaced. 1. Remove the two oil cooler line hoses and apply air pressure of 196 kPa {2.0 kgf/cm2, 28 psi} from the return hose (pipe) side. Caution Power ...

Mazda 6 Service Manual: Foreword
Caution When the engine does not start or stalls and the following DTCs are not indicated, go to engine symptom troubleshooting. Note When the immobilizer system is defective, the engine cannot be started. If engine condition is normal but light stays on, inspect for short circ ...