I bought this MDX from Carmax with a clean history. It did have 90k miles on it when I purchased. The car worked great for a few months but then I started to notice choppiness in changing gears. The vehicle lurches sometimes and will commonly get stuck in 2nd or 3rd gear (especially relevant when in sport mode). I have had this addressed by Carmax and they claim that it is working as intended? Is that right? Because I feel like no engine is meant to get stuck in a lower gear redlined out.