2008 KIA RONDO Engine And Engine Coolingengine Problems

ACCELERATOR IS "DRIVE BY WIRE". THE ENGINE EXPERIENCES HESITATION, WHEN TAKING OFF FROM A STOP, ABOUT 50% OF THE TIME, WHEN THE AC IS ON. SOMETIMES THE VEHICLE BEGINS TO ACCELERATE, THEN THE ENGINE DROPS TO IDLE SPEED, EVEN WHEN YOU DEPRESS THE PEDAL TO THE FLOOR. THIS CAN CAUSE YOU TO BE STRUCK BY ONCOMING TRAFFIC, WHEN YOU ARE ENTERING A HIGHWAY OR ROADWAY. USUALLY THE VEHICLE WILL THEN TAKE OFF UNEXPECTEDLY SCREECHING THE TIRES, WHEN THIS OCCURS. BUT, SOMETIMES, WHEN IT DOES BEGIN TO ACCELERATE AFTER ONE OF THESE OCCURRENCES, IT WILL VERY SLOWLY BEGIN TO PICK UP SPEED, AS IF IT IS STARVING FOR GAS. THIS COULD ALSO PUT YOU IN DANGER OF BEING STRUCK FROM ONCOMING TRAFFIC. THESE OCCURRENCES ARE WORSE, WHEN THE AIR CONDITIONING IS ON. SOMETIMES, WHEN YOU ARE TAKING OFF FROM A STOP AND PUTTING VERY LITTLE PRESSURE ON THE ACCELERATOR PEDAL, THE...

I HAVE A 2008 KIA RONDO LX (V6) WHICH HAS AROUND 6300MILES. I AM THE FIRST OWNER AND DROVE IT FOR THE LAST 6 MONTHS. EVEN EPA FUEL ECONOMY ESTIMATES ARE 18 MPG (CITY : 14 TO 22 MPG) AND 26 MPG (HIGHWAY: 21 TO 31 MPG) AT THE WINDOW STICKER, THEY WERE NOT REALISTIC. I DO NOT COMPLAIN ON CITY MPG AND IT IS 19-20 MPG IN AVERAGE BUT IN HIGHWAY MPG, IT WAS VERY DISAPPOINTING. I HAD SEVERAL TRAVELS WHICH TAKE 2 HOURS AT THE SPEED OF 65-70 MPG. EVERY TIME, IT WAS 21-22 MPG IN AVERAGE. THE BEST ONE WITH 65 MPH USING CRUISE CONTROL WAS 23.2MPG. I HAVE NEVER HAD 31 MPG AT ALL AS WELL AS HIGHWAY AVERAGE MPG OF 26. SO I THINK THAT KIA A LOT OVERSTATED THE HIGHWAY MPG. *TR