My car lunges forward after I stop and take my foot off the brake
What is your idle RPMs with car in gear and foot on the brakes?
I am not sure what you are trying to describe but if you are original owner you should still be in the warranty period.
The warranty transfers with the vehicle. It doesn’t matter if he’s the original owner or the 5th owner, as long as the vehicle is within the warranty period, he’s covered.