Hello - I am new to this forum. Had my 05 Tucson since 6/06. Bought off the lot for a good price since prior year model. Had no problems up until now. Just hit 40,000 miles. And over the last month, have had a couple of issues with acceleration. First time it happened, I was going down the interstate at about 70mph and then all of the sudden the acceleration died. Car went from 70, to about 30mph. Was able to get to side of road w/o getting run over and had my foot to the floor with the gas pedal just to get the car to move. Engine was "missing" but never stalled. Had no power at all. Finally got to gas station and let it idle in park. Pushed the gas and the engine rev'ed up. Put the car in drive and no power. Shut it off for a little bit and started again. Car is fine. My dad checked the air filter and it was slightly dirty. So we put a new one in about 3 weeks ago. No problems. Until today. Same thing - on interstate, lose power, etc... Does anyone have any idea what this could be? No engine lights come on, no overheating, nothing!!! Sorry to be so lengthy, but wanted to get an idea before i took to dealer and they tell me its "nothing"