Throttle body sucking oil into the engine

There shouldn't be "heavy sucking of air into the TB" when the hose is disconnected unless your air filter is totally blocked. Try removing your air filter and retest. However, excessive crankcase pressure can cause oil to be pushed out of the breather and into the throttle body. This can be caused by worn rings or worn valves, oil sloshing (hard cornering), or too much oil in the crankcase.

A bad PCV can cause excessive oil to accumulate in the intake and throttle body. First check for bad vacuum lines. Second replace PVC. Third, check vacuum pressure and make sure the needle on the vacuum gauge is not bouncing. Fourth, check cylinder compression in each cylinder. Fifth, make sure the intake manifold gasket is not bad. Sixth, make sure you have a good air filter and all vacuum line's are connected properly. Seventh, make sure the intake air control valve on the throttle body is working properly. Eighth, properly clean the throttle body and replace the throttle body gasket. Ninth, make sure there are no other bad engine gaskets. Finally, use a head gasket test kit to make sure the head gaskets are good. If the head gaskets are good, the test kit die should stay blue in color.

The simplest answer to all this is to replace the valve cover and which is cheaper when you buy it online ,and it is also cheap to replace it yourself you don't need a mechanic. The other way is to buy the pcv valve and replace it.The valve is located inside the top of the cover but it not easy to remove due to all the heat of the engine, and note these parts are plastic hence I recommend replacement of the cover, which is much easier.