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Losing coolant like magic

Every time I get ready to drive I have to put coolant In once I get back to the car the coolant is gone like magic there are no leaks. Just changed the hose’s and the tank so there aren’t any leaks help please

Radiator cap or head gasket or leakng hose my guess, no magic just mechanical parts

You need to have your cooling system checked out and possibly pressure tested. The fact that you think there is magic involved means that you are not the one to do it.

The magic part wasn’t a real statement.! It was just said because I feel like the coolant is just disappearing and idk why I’ll take it in to see what the prob is I just thought someone on here could give me an idea before I did take it in thanks oldtimer_11

The coolant is totally gone from the car just sitting with engine off? that seems to be what you are saying.

then there has to be a big puddle under the car. Did you check for this?

Is the car running normally otherwise? Any error codes, ie red warning lights on the dash?

Sounds suspiciously like a blown/leaking head gasket. If this Malibu also happens to have the 3,1L, then I would check out the intake manifold as well.


Coolant expands when hot and raises the level in the reservoir. Then when the engine cools, it draws coolant back in and the level in the reservoir drops. Routinely finding it low in the morning suggests that either you’re misunderstanding the “cold - hot” lines and filling the reservoir too full, coolant is being forced out a leak when it’s hot, or coolant in your engine is being displaced by combustion gasses.

Ergo, you have a leak in the cooling system, you have a breech in the headgasket, or (and I hope it’s this one) you’re overfilling the reservoir and expecting the level to stay there.
The first possibility can be checked with a system pressure check.
The second possibility can be checked by testing the coolant for the presence of hydrocarbons, doing a pressure leakdown test on the engine, or often by simply watching the coolant (cold) with the radiator cap off and the engine running. If it’s bubbling, you probably have a leaky head gasket.
The third possibility can be checked by (1) reading the owner’s manual and (2) looking with a flashlight at the side of the reservoir. You should clearly see the “COLD and HOT” words & lines molded into the bottle.

As he usually does, mountainbike has explained the possibilities very clearly.

However, what is not clear to me from the OP’s statements are the following points:

Does “gone like magic” mean merely that the coolant level in the overflow reservoir has dropped to some extent, or does it mean that there is NO coolant remaining?
Does this phenomenon take place after driving the car, or does it happen as the car sits, without the engine having been started?

I agree with this.

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Did this start right after changing the hoses and the tank or did you change the hoses and the tank in an effort to stop the coolant loss?

Me too. These are excellent questions, the answers to which can help us help the OP.

Seems to me that OPs with vague questions tend not to return and clarify their questions. Perhaps embarrassed?

To the OP (Original Poster): we are just trying to help. But we need more information. Please help us help you.

there isn’t a puddle that’s why I said I do t think there’s a leak and the car runs just fine other than the coolant disappearing after I turn the car off once I get back to the car after work the coolant tank is completely empty and there are no signs of a puddle under the car at all

To clarify; does the engine lose coolant when it’s running like you put coolant in it, then drive it, and then when you get back the coolant is gone. Or can you put in the coolant in it, not start the engine, and then come back the next, without the car being started or driven, and the coolant is gone.

It means there is no coolant in there and once that happens the heat gage will begin to rise and if I dont put anymore coolant in there it will over heat usually I’ll stop before it does overheat strong text and put the coolant in before it over heats. And this all happens regardless of the distance of my trip wether I’m just going right up the street or if I’m driving to work which is a ways away I’m just trying to get a small understanding of what could possibly be going on before I take it in to be evaluated

It disappears sometime after I park the car. I always check to see if it has any in there once I reach my destination and it will have almost the same amount I put in before I started driving .

I’m with @FoDaddy on this

If you have the 3.1 V6 . . . it was a very common engine for several years on the Malibu . . . there’s a very good chance the intake gaskets are bad, letting coolant into the crankcase, which is going to cause all sorts of trouble, including overheating

Check your coolant reservoir when the engine is cold . . . does it look like grimy and oily in there?

Check your engine oil dipstick. Is the level way higher than normal? Does it look like moccha frappuccino from starbucks?

One last thing . . . it’s possible you do have an external coolant leak, such as a waterpump, but you’re not seeing it because you’re not underneath the car. Do you have a jack and jack stands?

Even better would be if you could drain a little bit of engine oil into a tub and post some pictures

It appears that it is the overflow reservoir that is being emptied, not the radiator.

If engine oil looks good on dip stick, most likely a head gasket is leaking. Get it to a shop.

One thing is certain. It has to be going somewhere. A small coolant loss (like a cup every week) could be caused simply by a seal weeping and the coolant that leaks out just evaporates into the air from the engine heat. That might appear to be a mysterious invisible coolant loss. You’d usually notice a sweet coolant odor when parking the car if that was happening. But this doesn’t sound like a small leak.

hmm … here’s a theory anyway. You say the plastic overflow bottle after a drive is about the same level as you filled it earlier in the day. But it should actually be more full after a drive. B/c coolant volume expands with temperature. So you must be losing the coolant somehow during the drive. Then as the engine cools down what’s left in the bottle is sucked back into the radiator to replace coolant lost during the drive. So where is this fairly large volume of coolant going during the drive? Several possibilities

  • Leaking externally onto a hot surface like the exhaust manifold or exhaust pipe and evaporating. check the engine compartment for coolant odors.

  • Steam escaping from the radiator. check the radiator cap and have the cooling system pressure tested.

  • Leaking into the crankcase. check to see if oil level on the dipstick is going up for no apparent reason.

  • leaking into the engine air intake path via the throttle body or intake manifold. you’d probably see some white smoke out the tailpipe if that was happening, but maybe only high engine load conditions, like accelerating up a hill

  • Leaking into the combustion chambers via a faulty head gasket. usually this would produce white smoke out the tailpipe too. but no need to guess, shops have methods to check for that. that kind of leak often goes in reverse too, the exhaust gasses leak into the coolant, easy enough to do a coolant chemical check for that.