A composition for the manufacture of temperature resistant and sound attenuating automotive parts includes polyethylene terephthalate resin, basalt fibers, and mica. The basalt fibers and mica may be between 35 and 40% of the composition by weight of the total composition. The basalt fibers may be between 20 and 30% of the composition by weight and the mica may be between 5 and 15% of the composition by weight. The basalt fibers may be 25% of the composition by weight and the mica may be 10% of the composition by weight. A method is disclosed for molding a temperature resistant and sound attenuating part by blending a foaming agent with a thermoplastic olefin, basalt fibers and mica to form a resin mixture. The resin mixture is injected under pressure into a die to fill the die. The pressure is reduced to allow the foaming agent to form a microcellular core.