ALL TALK NO ACTION....

I own a 2005 Saturn Vue with 234579 original miles on it. It runs great until about 3 Weeks ago...
It's only good for one-way travel. Once I turn it off it will not start again until it sits for approx 6 hours or longer. The engine turns over but doesn't start. Computer sends no codes and doesnt display anything when scanning for codes.
We thought it needed a new ECM but after installing a new one we have the same problem again. Any suggestions??

 

Crankshaft position sensor.

Confirm no spark and no fuel getting to the injectors when this problem is occuring.

Sensor has a break in its coil. Coil is continuous when its is cold start and when being air cooled while driving down the road. You park it, the coil heats up and expands and it loses continuity at the break. ECM kills spark and injector pulses so you have no spark and no fuel. This is to protect the engine because the computer has no idea where the crankshaft is in its rotation so it doesn't want to be firing the spark plugs without knowing where the pistons are in their travel.

Source part from somewhere other than advance or AutoZone.