Intake temperature management systems for compression ignition of small molecule fuels

An engine, comprising

• a first flow path;
• a charge air cooler;
• a first valve configured to allow, block, or restrict flow through a passage between the first flow path and an inlet of the charge air cooler;
• a second flow path;
• a second valve configured to allow, block, or restrict flow through a passage between the first flow path and the second flow path;
• a third flow path configured to route flow from at least one of the first flow path or the second flow path to an intake manifold;
• a plurality of cylinders;
• an EGR valve configured to allow, block, or restrict flow through an exhaust path between the exhaust of the cylinders and the third flow path;
• an intake manifold fluidically coupling the plurality of cylinders and the third flow path;
• and
• a heating unit disposed at a location along at least one of the second flow path or the third flow path.