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View Full Version : "surging" '08 scion tC


tonyscan
05-27-2008, 03:39 PM
I have a new 2008 tC, now with about 2000 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?

burstaneurysm
05-27-2008, 04:03 PM
VVT-i is always working. It doesn't 'kick in' like VTEC or something like that.
It might just be trying to determine if it should be in 3rd or 4th (assuming it's an auto).

tonyscan
05-27-2008, 05:16 PM
It is an automatic, so I know it's in overdrive, (4th gear), which happens at about 40 mph. Why it "hunts" at around 60 beats me! Thanks anyway.