When I push the accelerator in my QX4, I feel the car pull back a little. So even if I am driving on a level road, it still feels like I am driving uphill all the time. Any ideas on what might be wrong? I have had this problem for a really long time and every time I go to the dealer/different Infiniti dealers, they keep replacing stuff. I just had the belts and the muffler replaced. In addition, there was also an oil change done.