It won’t start in the cold, new battery, checked alternnator, battery good, If it gets too too cold in winter will not start, but you can jump it and it will start. Please help
Just think of what happens when the jumper cables are attached to your battery cable terminals: your battery is almost completely bypassed. The power can’t get out of your battery through the corrosion between the battery posts (terminals) and the battery cables. Disconnect the battery terminals and scrape, sand, abrasively remove the corrosion from the inside loops of the battery cable terminals and the battery post (or, terminals). Wipe the posts and terminals with Vaseline, and reconnect the cables. Charge the battery, if needed, and away you go!