Topran Crankshaft seal (1.4) Jetta (1.4TSI)

Engine Camshaft Seal
A camshaft seal is a rubber or silicone ring located on the top of the cylinder head near the back of the engine, designed to prevent engine oil from leaking out; a failing camshaft seal will most noticeably manifest as visible oil leaks around the back of the engine, sometimes accompanied by smoke from the engine bay when the leaking oil comes into contact with hot exhaust components

Engine Camshaft Seal Failure Symptoms
Visible oil leaks: The most obvious sign, usually seen on the back of the engine near the valve cover.
Smoke from the engine bay: Oil leaking onto hot exhaust manifolds can burn off, producing smoke.
Oil residue on the engine: Even small leaks can leave noticeable oil stains on the engine.