LYNN – Sub-zero temperatures can make your car complain loudly.Whether a cough, sputter, groan or weak sigh as you turn the start key, bitter cold can stop your car in a hurry.But local mechanics say motorists can take precautions to lessen the odds of a breakdown.”If you have a borderline battery, it’s going to crank slow and crank until it dies,” Tom Kasper, owner of Pudgy’s Towing and Auto Repair on Pleasant Street, said Monday when the temperature in Lynn was -2 Fahrenheit. “You have to pay attention to all the fluid levels in your car, including what’s in the battery. We had a lot of dead battery calls today.”Kasper advised motorists to check their anti-freeze fluid levels.”Make sure it’s good or you risk motor and internal damage if it freezes,” he said.Several customers had no heat in their automobiles. “No heat is a common problem when it’s cold like this, but we don’t see as many cars that won’t start. The newer cars have fuel injection and are computer-controlled. The days of points and condensers are gone, so you have a lot better chance that your car will start,” Kasper said.Kasper dismissed as myth the suggestion that a car key should be turned clockwise until the dashboard indicator lights switch on and only then cranked fully to start. “Just turn the key and start the car,” he said.Kirk Neumann, manager of Wilson Square Citgo at 2 Andover St. in Peabody, advised motorists to run their engines before going to bed if the forecast calls for extreme cold.”It’s a good idea to keep the fuel topped off, but not as necessary with the newer cars because the gas is already treated. If you have an older car, say 15 years or more, you should probably put a can of dry gas in the tank,” he said.According to Neumann, batteries bake in summer, causing them to dry out. “If you don’t have your battery checked until winter, it might be too late,” he said. “Most batteries today are maintenance-free. They still have caps for the fluid, but don’t touch them. And don’t add any fluid. Let the garage do that.”Neumann also recommended keeping the windshield washer fluid reservoir filled. “The more washer fluid you have, the less chance it will freeze,” he said.Rick Starbard, owner of Rick’s Auto Collision and Service, 655 North Shore Road in Revere, suggested wearing goggles when attempting to use jumper cables to start an automobile. “If you need to jump start your car, remember that battery gases are explosive, so you have to know there is a proper order to do it,” he said.Starbard emphasized jumper cables cause sparks, which can ignite leaking battery gases and result in an explosion. “If you’re going to jump start, first connect the positive cable to the positive terminal on the good car, then connect to the positive terminal on the bad car,” he said, explaining the third step is to connect the negative or black cable to the negative terminal on the good car. “The last one clamps to something metal on the bad car in order to ground it.”The alternator bracket should suffice, he said, adding, “The better it’s grounded, the less chance of explosion.”As for taking care of your car’s body in winter, Starbard said get the salt off the undercarriage quickly by running it through the car wash and selecting that option.