Catalyzes the hydrolysis of acyl-CoAs into free fatty acids and coenzyme A (CoASH), regulating their respective intracellular levels (By similarity). Displays higher activity toward long chain acyl CoAs (C14-C20) (PubMed:7744868). The enzyme is involved in enhancing the hepatic fatty acid oxidation in mitochondria (By similarity). H2O + hexadecanoyl-CoA = CoA + H(+) + hexadecanoate H2O + tetradecanoyl-CoA = CoA + H(+) + tetradecanoate H2O + octadecanoyl-CoA = CoA + H(+) + octadecanoate eicosanoyl-CoA + H2O = CoA + eicosanoate + H(+) decanoyl-CoA + H2O = CoA + decanoate + H(+) dodecanoyl-CoA + H2O = CoA + dodecanoate + H(+) (9Z)-octadecenoyl-CoA + H2O = (9Z)-octadecenoate + CoA + H(+) (9Z)-hexadecenoyl-CoA + H2O = (9Z)-hexadecenoate + CoA + H(+) (9E)-octadecenoyl-CoA + H2O = (9E)-octadecenoate + CoA + H(+) (9Z,12Z)-octadecadienoyl-CoA + H2O = (9Z,12Z)-octadecadienoate + CoA + H(+) Optimum pH is 8-9. Lipid metabolism; fatty acid metabolism. Monomer. Constitutively expressed in heart and brown fat. Strongly induced in liver, and weakly in kidney, in peroxisome proliferator treated rat. Regulated by peroxisome proliferator, via the peroxisome proliferator-activated receptors (PPARs). The N-terminus is blocked. Belongs to the C/M/P thioester hydrolase family.