My car will violently downshift around 1 rpm. It does not happen all the time but once it happens it will do it for the rest of the time i drive it for that day. Letting it sit over night usually will cure the problem temporarly. I have taken the car back to the dealership and they reset some sensor, Any thoughts from anyone?????

 

Presumably you are referring to harsh downshifting at around 1,000 rpm (as opposed to 1 rpm). What year is the car? If a 2005, has the DME re-program service campaign been performed? If the car is brand new and still in break-in period, then you could be going through a learning process where the transmission is still responding to factory default settings (one of which involves maintaining engine speed during downshifts (especially if you are driving downhill)). Perhaps you could provide more information - year of the car, CVT vs. traditional a/t, miles, driving scenario(s) when the harsh downshift occurs, etc.?

 

sorry, yes at 1,000 rpms

Anyway the car is a 2006 and i bought it in January. The car is past the break in period and honestly I don't remember it doing this in the break in period or at least it wan't this drastic. I am having trouble with the cold start problem, do you think the two may be related??? Any thoughts are welcome!

 

Is your MCS an automatic, or manual (stick-shift) transmission?

My MCSa (automatic) had quite harsh downshifts at first, but then I used the paddle shifters to "teach" the car when to shift and it's been butter-smooth ever since. Well not exactly butter, but it's definitely acting like a normal automatic transmission should...no harsh shifts or shift-shock...

If it persists, it might be best to bring it to your dealer and leave it with them for the day so they can have a mechanic drive it around a bit to determine what the problem could be...

 

It is an automatic.
Thanks for the advice