PCV is connecting with Crank case or lets call it near to Tappet Cover. Normally it has very long life. But it has found clogged in few cases.
T-Valve is Thermostate Valve. When engine reaches slightly above than its optimum temperature, the valve opens automatically and allows more water to circulate throughout the engine. In many cases, the mechanics removes the T-Valve and connects the fan directly. This is really not good for engine.
10w-40 is not recommended for 1KR-FE.
Next time keep it on low viscose oils like 5w-20 or 5w-30. Don’t go for 40 or 50.
Are you from Lahore ?