A monolithic, multilayer heating element (26, 126, 226) forms the high temperature tip (22, 122, 222) of a glow plug assembly (20). The heating element (26, 126, 226) includes a conductive core (48, 148, 248) which is surrounded by an insulator layer (50, 150, 250), which in turn supports a resistive layer (52, 152, 252). An optional conductive jacket (172) can surround the resistive layer (152). These layered components are pre-formed in prior operations and then assembled one into the other to form a precursor structure. The precursor structure is transferred to a die (54, 64, 164), where it is compressed to fom a so-called green part having dimensional attributes proportional to the finished heating element (26, 126, 256). The individual layers remain substantially intact, with some boundary layer mixing possible to enhance material-to-material bonding. The green part is sintered to bond to various materials into an essentially solid mass.