Impreza 06 loosing power while accelerating!!

[Domagoj]

So basically i got a new cat, new o2 sensor, everything was fine..but car started to lose power while accelerating and when i reset ECU the car runs fine for about a month and then starts to lose power again..anyone help?

 

[Clover]

Might want to check for an exhaust leak after the Cat was replaced. It could be a few things, but if you just had that done, it seems like a logical place to start. An exhaust leak can also cause the air fuel ratio to be off. You could also check your mass air flow sensor and clean it. If that sensor is off, it could also cause problems, maybe even the misdiagnosis of cat/O2 exhaust problems. They are normally easy to get to on the air intake going into the engine. There is special MAF sensor cleaner which I would recommend over brake clear or something not designed for it. Good luck.