After seeing a post on the 986 Forum called "Knock Sensor Help" by Miles1, today I removed the front engine cover and used a flashlight to inspect the wires/harness from the knock sensor behind the alternator (see link/image below). Low and behold, I have the same issue - the wire at the connector attached to the knock sensor was frayed/broken. No telling how long this has been going on, since it does not illuminate the CEL. Looks like I will need to have the Knock sensor connector/wires replaced and the part I need is available on Parts Geek...
After seeing a post on the 986 Forum called "Knock Sensor Help" by Miles1, today I removed the front engine cover and used a flashlight to inspect the wires/harness from the knock sensor behind the alternator (see link/image below). Low and behold, I have the same issue - the wire at the connector attached to the knock sensor was frayed/broken. No telling how long this has been going on, since it does not illuminate the CEL. Looks like I will need to have the Knock sensor connector/wires replaced and the part I need is available on Parts Geek...