1992 Nissan Maxima problem- engine clicking. camshaft issue?

[TheLetterK]

Check engine light went on today with a cyclical clicking that is louder upon idling coming from left side of engine. At first the sound reminded me of low oil, but oil was fine. Opened the hood to listen for where sound was coming from. Felt and listened around to hone in on it. The hex shaped thing that the camshaft position sensor attaches to on the upper left corner of engine is vibrating pretty hard and that's where the clicking seems to be coming from. Car slightly vibrating too. Is it safe to assume that the camshaft position is off? What would cause it to not be in position? Is this an easy repair to do myself? I'm afraid to take it on the highway because I don't know how severe this type of prob is.
Modified by TheLetterK at 12:33 AM 7/4/2009

[MinisterofDOOM]

Is it an SE? If so, it's probably the variable timing control (VTC). It's a common problem with the VE30DE motor.

Here's a good thread on the subject:zerothread?id=292004

[TheLetterK]

Yes, an SE. Perfect! If it's not a dental emergency it's a car thing! How much can I drive it before I'm screwed on the side of the highway? I'm afraid to drive it just to get home, an hour away on the highway.

[MinisterofDOOM]

It won't harm anything, but if the VTCs fail completely you'll lose variable timing and with it some power.