Yaar I am a novice but as far as I believe, ur car's engine is growing old due to rough use... I have got a 2008 GLi and I put 135000 kms on its ODO, but still, it does 185 with ac and cng...
were u the first owner of the car or bought it as a second hand??
suppose u are its first owner and the mileage is flawless, then what i would strongly recommend is that take ur corolla to Toyota's service shop and get it maintained from there... they will check the pistons, spark plugs, lubricants, etc etc on ur car... they will cure the problem to 95% at least...
Drive safe bro....