This was posted on w-body.com earlier in my thread:

Somebody PLEASE tell me this isn't a possibility with a 3800.

I have never heard of it happening. The cam bolt would have to come loose. that would allow the cam sprocket to move. But the crank sprocket wont be able to move because it'* held in place by the oil pump. So the cam sprocket should stay in place.

Thank you. That'* what I wanted to hear.

To be completely honest, this whole problem has me worked up like crazy. I lose sleep over it. It annoys the living hell out of me that my engine vibrates under idle and that I have that stupid ticking noise. I feel like tearing the engine apart bolt by bolt to figure out what it is, but I don't have the time for it. I'm hanging by a thread hoping that the tune is what'* throwing everything off and that my knock is legitimate preignition, not some other loose mechanical part in my engine throwing off the sensor, like a loose camshaft, God forbid. I pulled the cam sensor to look at it and its in perfectly untouched condition.

Deep down somehow get the feeling that some invisible entity is trying to tell me to swap in an L67...

The whole reason this idea came up was because the car threw a code 342 today, camshaft sensor, which went away after I shut the car off and started it back up again. Evidently the code 342 only comes on when the car doesn't receive a signal from the cam sensor for at least 5 seconds.

Have you checked your flex plate and harmonic balancer? Other then those the only possible vibrations could come from the balance shaft being off. But that can only happen if you removed it for a rebuild and put it back together wrong. Easy to do if your not watching. But that can not happen on it'* own.

The harmonic balancer isn't wobbling. I did check that. What'* the flex plate and where is it?

I only removed the heads, not the timing cover or the balance shaft. I didn't touch either of those.

I can't begin to tell you how much I appreciate your help here.

I'll get a new video tomorrow so you can see what the engine sounds like at idle after a drive. Its a strange sound.

For now, have a listen at this again. Listen to the idling, and let me know if you hear anything unusual. Almost sounds like a diesel.

http://www.youtube.com/watch?v=m-C4lXnz5ho

Flex plate is the fly wheel.

Haven't touched that at all, so I don't imagine it could be making any noise. Do those randomly start vibrating out of nowhere? What do you make of my idle?

I had another thought. Have you done a compression test? If one cylinder is off it can cause vibration.

Can't say that I have. I figure I might as well at this point, although it doesn't make sense since the head gaskets are new. Unless I had a stuck lifter that was keeping a valve slightly open the whole time. I'll check compression tomorrow.

Other then that all I can think of is a bad motor mount.