No acceleration on inclines?

This might be a simple problem but I cant tell what is causing it.
2.5L V-6. Automatic.


Sometimes, usually when going up hills or inclines, I cannot accelerate like usual. If I push the pedal to the floor, there is no noticeable reaction from the engine, but the car can maintain its current speed. If Im going a certain speed on the highway, and I reach a slight upward incline, it takes a while to reach a speed to pass a car in front of me. RPMs dont go up and speed doesnt change. The delay lasts until the road levels out. Im guessing its a fuel delivery problem of some sort but Im not sure. On level roads the acceleration is good and there are no problems. Seems to happen regardless of weather conditions. Any ideas?

Check your transmission fluid level. It wouldn't hurt to replace the fuel filter. Those are the cheaper fixes to try first.