2007 lincoln mkz w/ 40k miles well-maintained. on four separate occasions approx 3 months apart, when engine still somewhat cool and within 5 miles of start-up, vehicle is stopped in drive with foot-brake applied. engine suddenly revs and car begins to accelerate, despite application of hard brake pressure. to avoid collision, driver must shift to neutral or park and turn off engine. still under warranty. dealer (1) downloaded and applied computerized updates, (2) changed battery, (3) reviewed all online and ford moco bulletins but found nothing relevant. problem is very serious but occurs only intermittently & dealer cannot duplicate. driver has contacted ford/lincoln in detroit and opened a case file to research & track problem. most recent occurrence on feb 28, 2010, at 3:00 pm. car taken to dealership on 03/01. dealer will have regional ford engineer examine vehicle. *tr