New Owner - Hard Panic Stop Question

[Bassin34]

I just purchased a 2009 Versa SL (CVT) and had a hard/panic stop question. I searched this issue on the site and read that some people have had this problem, but there hasn't been any info since 2007. Today, I had to slam on the brakes to avoid someone making an illegal turn. I swerved to the right and slammed on the brakes. When I put the car in reverse to get back on the road the car wouldn't move. It felt like the car was in neutral. I then put it into drive and tried to move forward and the car would barley move, but did go forward enough for me to pull in to the adjacent gas station. I turned the car off and waited a few seconds before restarting. The car moved better, but did take a few minutes before it was performing better. I remembered reading something about hard braking issues when I was researching the car prior to purchasing it, so I didn't totally freak out when this happened. However, I wanted to know if this type of reaction by the CVT is indicative of a problem or is it something that I just have to deal with when it happens?

[BBISHOPPCM]

What you experienced isn't entirely abnormal. I say this because you experienced something a little different than the usual...

Normally, if the wheels slow down too quickly, the transmission compensates for this by throwing it into "first gear." This is because unlike a traditional automatic, the CVT uses a steel drive belt that rides on two adjustable pulleys. In order for this system to work properly, the pulleys need to adjust the drive ratio according to the speed sensors. When the speed sensor sees you traveling at 50 MPH little throttle input, the transmission will automatically position the pulleys to give you a larger drive pulley and a smaller driven pulley. The same works in reverse; if the car suddenly slows down from, say, 30 mph to zero, the transmission compensates by forcing it into a much lower gear, if not the lowest. What the Versa has is sort of a "panic" or "limp" mode; this is usually activated if the ABS system kicks in, or of the wheels suddenly lock up in a panic braking situation. This will cause the transmission to hold the low gear position for several seconds after a panic brake incident. This is normal, and I believe it is designed to help slow the car down to assist the braking system. By throwing yours into reverse, you may have confused the system to a certain degree. As long as it's working fine now, you likely have nothing to worry about. This system saved my life last winter, when I suddenly hit a patch of ice.

[Bassin34]

Thank you for responding and for such a detailed response. The car is only a week old and I was hoping this wasn't a defect of some sort. Thanks again for putting my mind at ease.