Possible Causes

WARNING: This page is about a different car, the 2003 Dodge Dakota. However, it is still accessible from the selected car via links, so may be relevant.

Intermittent Crankshaft Position Sensor Signal
Intermittent Camshaft Position Sensor Signal
(K6) 5-Volt Supply Circuit Shorted To Voltage
(K6) 5-Volt Supply Circuit Open
(K6) 5-Volt Supply Circuit Shorted To Ground
(K44) CMP Signal Circuit Shorted To Voltage
(K44) CMP Signal Circuit Open
(K44) CMP Signal Circuit Shorted Ground
(K44) CMP Signal Shorted To (K6) 5-Volt Supply Circuit
(K4) Sensor Ground Circuit Open
Camshaft Position Sensor
PCM