WHEN STOPPED IN TRAFFIC CAR HESITATES, STALLS AND STUMBLES TO ACCELERATE FOR A FEW SECONDS. UNABLE TO SHIFT FROM 1ST TO 2ND SMOOTHLY (STUCK IN 1ST GEAR?). WAS REAR ENDED WHEN UNABLE TO ACCELERATE AT LIGHT. DEALER DID SOFTWARE UPDATE THAT DID NOT FIX PROBLEM, STILL ONGOING