Problems with 2005 Hyundai XG350 ENGINE AND ENGINE COOLING

Car driven for 6 miles. engine shut off for 1 hour. restarted car and shifted to dive. car moved forward without problem. traveled 3/4 mile and stopped at traffic light behind some cars. had right foot on brake pedal, car started to move forward, pressed pedal harder but car continued to move forward. noticed rpms at 4000 without gas pedal being touched. shifted to neutral, depressed and released gas pedal. rpms at 3500 and dropped to 1000, rpms jump to 3000 and back to 1000, rpms jump to 2500 and back to 1000, rpms jump to 2000 and back to 1000, rpms jump to 1500 and back to 1000. this process took about 25 seconds. put car in drive, all seemed ok very bad situation. ***note: car temp was slightly below normal **** *jb

Seven instances of unwanted engine acceleration since jan 2006. all occurrences similar: 1)engine is warm after a period of driving; 2) car decelerating approaching stop sign, traffic light, or in stop-and-go traffic; 3) a barely audible "click" is heard and the engine rpm begins to rev up making braking difficult and giving a clue that something is amiss. when this point is reached key was turned off or idle selected to see how high the rpm would rev; 4800 is the highest noted. this is a random event as the car has over 10000 miles with 7 occurrences. latest date is noted below. *jb

Seven instances of unwanted engine acceleration since jan 2006. all occurrences similar: 1)engine is warm after a period of driving; 2) car decelerating approaching stop sign, traffic light, or in stop-and-go traffic; 3) a barely audible "click" is heard and the engine rpm begins to rev up making braking difficult and giving a clue that something is amiss. when this point is reached key was turned off or idle selected to see how high the rpm would rev; 4800 is the highest noted. this is a random event as the car has over 10000 miles with 7 occurrences. latest date is noted below. *jb

Initially (2) times there was no response from engine when gas pedal depressed, we have had 3-4 incidents of when stopped at intersection, or driving slowly in parking lot engine surges and breaks had to be applied severely to prevent car from hitting other cars, the last incident was the transmission would not shift from 1st gear and car would not go faster than 20 mph. all of these are safety issues. *nm

2005 hyundai xg350l intermittently stalls when put in motion, then rapidly accelerates and surges forward. *ts after a few seconds the vehicle will regain power and surge/lunge forward. the vehicle was taken to the dealer but they were unable to duplicate the problem. they replaced the throttle body but that did not rectify the problem. *nm

Throttle becomes sporadic and unstable. problem occurs once car has reached operating temperature and is restarted. this is a safety issue due to vehicle surging forward or not responding. manufacturer has not resolved this issue even after several attempts. *jb