"surging" '08 scion tC

[tonyscan]

I have a new 2008 tC, now with about 1500 miles on it, and I have noticed something that I can't find an answer to. This is my first VVT engine, (and only my second Japanese car in 20 years), so I am not "up on the technology", as I am with American cars. Maybe someone can help me.

At about 2500 rpms, (55-65 mph), although I am keeping the accelerator steady, I notice a "hunting" of the engine, which can vary by 200-300 rpms, on the tach. Some may also call it a slight "surging" and droping back. It's almost like when you activate the "cruise-contol", and the engine tries to maintain the speed that you have set. I looked up an explanation of "VVT' technology, and it seems that VVT does not come into play until approx. 6000 rpms.

Can anyone help me with an explanation, or with a similar problem?