Hello fellas!

I have an 04 impala that has 77K on it and yesterday it started having a problem. It seems to lose torque (by that i mean that it makes NONE going up hill) until it gets to 4th gear and even then it still doesn't pull as hard as it should. When the car is first turned on it is fine until it hits a certain point (it varies) and then it'* like the chain falling off on a bicycle, has a hell of a time making torque and it misses unless the slightest touch on the accelerator is used (the tach needle bounces all over the place). any ideas??

Is the CEL lit? Is it flashing?

no check engine light on, and when attached to a reader it spits out no codes

I'm thinking MAF sensor, but that seems to quick and sudden if its really dirty. Have you changed/added anything recently? Like added a air filter?

do you mean the trans is slipping? the engine revs and you dont go anywhere? the tach follows the engine or bounces independent of the engine?