The Altis engine DOES NOT need to be touched till well over 300,000km. YOu must have made some kind of a mistake somewhere that u needed to open the engine at such an early stage.. perhaps, lack of oil , maintainance ofr overheating.
ONly toyota dealers have the mechanics with the capability to work on a high tech engine such as that of ALtis. Do NOT drive your car. Have it towed to a proper toyota dealer for proper repairs