Compression Ignition DEMANDS that the engine be cranked as fast as possible. On the older 855 series Cummins, I ensured that when the owner pressed the starter button, even in 0F temperatures, the cab of the truck shivered as the 40MT was cranking. Cold air and compression ignition do not get along, hence glow plugs. When it used to drop to -30F I would remove the lid of the air cleaner and then the element. Heat up a 5 lb chunk of steel red hot with a rosebud oxy-acetylene torch, drop it into the aircleaner, put the lid on, wait a minute then have the driver crank the rig. Worked like a charm unless the fuel was gelled.