Chrysler Repair: 00 2.7L: code 1391, camshaft position sensor, crank sensor

Question
After the car warms up, It runs rough then it shuts down and I cant get it started until it cools down.  The engine is not over heating according to the gauge.  The Number that comes up over the odometer is p1391.  One mechanic told me it needs a new timing chain.  Another said a camshaft position sensor. Do you have any ideas?    Tom

Answer
Hi Tom,
The 1391 code is saying that there is an intermittent loss of either the cam or the crank sensor signal, as both are needed (or maybe something about the wiring or the mounting of those sensors, but those are not as likely as that one of the sensors is 'going'). Heating/failing then cooling/recovering is a symptom of such a problem and it will soon set either a 0340 (cam) or an 0320 (crank) code so you will know which one it is. The timing chain is out of the question, or at least very unlikely.
You could try probing through the insulation of each sensor's signal wire and the common ground wire using pins to touch the inner conductor, then attach a voltmeter to the pins, then turn the ignition to the 'run' position, then crank the engine over by means of a ratchet and handle by hand. You would expect to see the voltage reading change several times between 5V and 0.3V per revolution if the sensor you were looking at is good. You would do this during the 'shut down' situation, otherwise both will look good. The crank sensor wire is gray/black and the cam sensor wire is tan/yellow and you would put the common ground pin in the black/light blue wire. Those wires are also available at pin 32/33/43 respectively at the pcm plugs which may be more accessible.
Roland