Automatic 2-1 rough downshifting

wstar

Are you coming to a stop soon? Are you coming up on a corner? What's the min speed you intend to hit in the corner? Are you accelerating slowly right now for a few seconds (someone's in the way), but about to get on the gas right afterwards (there's an opening in another lane a few seconds away)? Are you accelerating hard right now, but intending to drop back off the gas considerably once you reach XX mph?

All of these sorts of things and countless others go through your head picking your current gear manually. An automatic transmission in D-mode really only has three basic input variables to work with for making a gearing decision for you: Current Vehicle Speed, Current Engine RPM, and Accelerator Pedal Position. That's true of any auto transmission, even on a minivan.

If your tranny can't make up its mind and settle on a gear, it's because your inputs (the 3 above) are fluctuating in patterns that don't make sense for what it's designed for. It can't possibly know all of the other factors in play. For everyday poking around in traffic, an automatic transmission makes reasonable gearing decisions for average drivers, focusing mostly on fuel economy, and trying to respond quickly with a downshift if you stomp the gas pedal hard to pass someone.

It should come as no surprise, especially in more complex situations, that an auto transmission makes poor or even schizophrenic gearing decisions. Use the M-mode, Luke.

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UNKNOWN_370

That I get when I accelerate fast n just stop push the peddle suddenly. The car revs up then higher, then I let go of the gas and press on it a lil for it to find the gear. Its kinda weird. It only happens once in a blue though

kidkotic2001

I believe that this is normal, I have the same issue I told the dealer they did not find any issue with it. I really do not switch to M mode unless I am on the highway in city I stick to D.

UNKNOWN_370

Yeah I'm not even concered with any of this. The CVT is just a weird tranny. I've owned four cvt's already. The performance is sick... knock on wood they have all been reliable, but they all had strange personalities unlike normal trannies. Infinitie gear ratios. Makes this car have to think on its toes. Sometimes she gets a lil confused. With so many gear ratios I totally understand her n it doesn't annoy me at all.
Sports cars are jerky. At least in my experience they have always been... maybe I don't spend enough money on cars? Or maybe I need to own german to appreciate a non jerky sports car??? Lol

DrEvil

Mine does the same thing. I just had the XC 70 out and it too has a manual mode. I noticed that it doesn't drop down into first untill the car has actually come to a complete stop, giving a smooth 2-1 down shift. I think that out ats' are programed that way to drop into first while the car is still moving.

waaaasabi

The 370Z doesn't have a CVT.

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