5.2 has been running flawlessly.
173k miles. Started this morning for about 1 second then died.
Cranks over fine.
Fuel system fine
Not the timing chain.
No spark.
All fuses and relays good.
Recent cap and rotor, wires, plugs.
How best to determine if coil? If crank sensor?
Thanks.

 

See if you have power at the coil while cranking. Should see power for about three seconds at initial key on, then again, when the engine is turning. If you don't get power back with the engine cranking, likely the crank sensor has failed.

 

Thanks!
will try!

 

Replaced Crank sensor.
Still no spark.
How to tell if ECM?

 

So if it's sending power to the coil. What brand Crank Sensor?

 

Echlin

 

Does power come back on when you try cranking the engine?

 

They could be the problem. Many members including myself have had issue with aftermarket sensors that was all fixed with genuine Mopar sensors.