I was having this trouble as well with my 14 pro max. For the first few days after the update, I would have to pair with the vehicle almost every time I drove. Seems to have gone away on its own, though. Try deleting the phone and re-pairing. I also set the device pairing order to "last connected device", or something along those lines. That might have helped but not sure. Problem is gone for me now, though.
Speaking of iPhones, it annoys me that I cant use a protective case on my phone and utilize the Qi charger at the same time... I upgraded a couple of weeks ago to the 14 pro max, and the phone charges fine without the case, but every case I've tried has a raised lip around the camera lenses (which are tall to begin with) and coupled with the added thickness of the case there is just too much distance between the phone and charging coils of the Qi charger to initiate a charge. I get the notification "Wireless charging not available." Are you experiencing this issue?