i have a very bitter experience with the engine of this altis, better sell the car or swap the engine, whatever 3s dealer says leave them. This engine is having hydraulic tappets, you have to change the both cams even for smooth running sound, plus the silver block is not suggested to be overhauled.
I also ended up in selling the vehicle way less than the market, some 3s dealer says its faulty crank, some says cam problem. some said pistons pins are loose.
I got it checked by toyota airport, walton, cantt.
I was like what the **** they are doing they all differ in dere statements.
Its better to swap, if not then sell it
Swapping is the only option, a big no for overhaul