P0700 Fault in 2008 Dodge Avenger 2.4L After Engine Replacement Due to Timing Chain Failure

I recently had my engine replaced due to valve damage caused by a slipped timing chain. The car was running normally for the first 50 miles, including several short trips over three days. However, while driving in heavy traffic, I experienced sudden brake pedal feedback and the vehicle lurched backward when accelerating. The shift indicator was showing 'D'. After pressing the brakes (and narrowly avoiding a collision with the vehicle behind me), when I released the brake, the car resumed forward motion. I managed to drive another 10 miles without further issues. Upon connecting a code reader, a temporary P0700 fault was detected—no check engine light illuminated. I've inspected the wiring connections to the Transmission Control Module (TCM) and found them intact. Could the issue be related to a defective component on the used engine that was installed? The mechanic mentioned that all original components from the old engine were left in place. Any insights into whether this could be a sensor or module issue on the replacement engine would be greatly appreciated.