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2000 Saturn black smoke out of exhaust/low antifreeze

What does it mean when black smoke is coming out of the exhaust and the antifreeze is low even after you put it in

Black smoke usually means the car is running “rich”, translation too much gas is getting into the cylinders. Since the car is a 2000 it could mean time for new plugs, or something more involved in the fuel delivery system. Is the “check engine” light on?

Low antifreeze, first question where do you “put it in”? And, how much did you add. If you just filled up the plastic overflow bottle, then air could have come out the cooling system and sucked the coolant from the bottle into the motor. In which case add more coolant to the bottle (don’t fill it more than 1/2 full) and run the car for a day or so as normal and check the coolant bottle again. You should be adding 50/50 mix of coolant and water which can be bought premixed which is best.

If your motor was low on coolant it might take several fills at the overflow bottle to get all the air out of the system. If this is too much fussing for you, take it to a mechanic to check the cooling system. If you are low on coolant there may be a leak or something more serious. Coolant leaking into the cylinder is serious but the result is usually white smoke from the tailpipe, not black.

Black smoke = a rich mixture, too much fuel
White smoke = water is going into the cylinders or even antifreeze
Blue smoke = burning oil

Thank you. What is the best place to put the coolant and do use the orange extended life coolant, does it matter?

I’m not sure what coolant this car was shipped with from the factory, but you can use the green stuff with no trouble as long as the system is flushed thoroughly. Definitely use what’s already in there if you’re not going to flush it.

Saturn losing coolant and you have to keep adding? These cars were known for head gasket failures. How does the engine oil look? I’d definitely have it checked out.

Not sure about the black smoke—this means the engine is running rich (getting too much fuel) as someone else posted. Is the “check engine” light on?

The check engine light is not coming on. The oil light comes on when the car is first started then turns off and the coolant light comes on. The car recently had an oil change, it does have a slow oil leak that is checked weekly.

What does the oil look like—does it look ‘normal’, clear amber or light brown? Or does it have the consistency of a milkshake? If it’s a milkshake, the engine is on borrowed time until the gasket is fixed. Either way, I’d have it checked out—Saturns are known for this.