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Does the engine go onto the second cam when it is in neutral?
As far as I know the cam changeover is only a matter of the engine being at the proper rpm for the changeover to occur, so yes, it should be possible to get the cam changeover to occur with the car in neutral. It probably isn't a good idea to be racing the engine at high rpm with no load on it and the transmission in neutral though.....
 

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Discussion Starter #3
I do not normally do it. I am trying to figure out why I have a cement mixer with gravel noise at about 6500 when moving. I've run the engine up while stopped in neutral but can't reproduce the noise. I was figuring that may be there is no change over if the engine is not under load.
 

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I thought the cpu handles the changeover, hence making it inteligent as in vvti-l. If so I would think it needs to be under a loaded condition? But I've never tried.
 

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I would guess the cam change requires a load. Do the ignition sounds seem to "line up" like they do when a working car changes over?

If one of us goes outside to try this, we will seem awfully dickish.
 

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Wouldn't it have to happen. What happens when you quickly shift at high RPM's on the 2nd cam to the next gear and are still in the high rpm range to stay on the 2nd cam. I would assume during your shift (you're in neutral) that the engine remains on the 2nd cam.
 

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Load and RPM are required. If you get onto second cam in 1st, then pop the clutch in and keep the revs high, it should transition back to the small cam as the load goes away. It doesn't happen between gear changes as there's a threshold/delay involved.

Your best bet for finding your sound is a dyno, however if there were enough valve train damage to be causing significant "unhappy" sounds while driving, chances are they would be at least somewhat present under other conditions as well. You can always pop the valve cover and have a look.

My guess would be something transmission/driveline related, or a resonance thing with a heat shield or exhaust part or something similar.
 
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