Where is the speed sensor located on a 2012 Chevy malibu, automatic, 2.4?

Try the back of the transmission. There should be a wire running to a sensor back up to the dash.

2011 Malibu speedometer don,t work and transmission will not shift trans starts off in higher gear real sluggish

GuruTWDP, I never really understood automatic transmissions, and now the new ones are computer enhanced to adjust shifting points and even shut down the transmission or engine if there are conditions that may cause damage to the tranny or engine. My wife's older MBZ will if the fluid is low, not allow it to shift out of first gear. First I'd have the computer read to see if there is a sensor needing replacing, check the fluid levels if you can, and have the computer itself diagnosed before tearing into a $10,000 (maybe) repair of the tranny. Since the speedometer also will not work, that may indicate it is electronic, not physical.

electric trans speed sensor bad can cause speedometer to jump or not work also car to shift hard or stay in second gear. other dash warning lights may appear such as service engine or power steering light this part cost is about 15 to19 dollars and can be replaced by any mechaniclly handy person. you may need to have codes reset

All issues relate to VSS, replaced. Did not fix, although no sensor error now.