Our 1999 Aurora looses colent, not a lot, not even enough to see leakage on the ground. I have replaced all hoses and flushed the Radiator. There is no leakage I can find on the inside like it might be a heater core. I am stumped. I have to top off resavore about once a week.

Check your oil is it milky white? Or smell your exhaust with engine running does it smell like coolant?

Generally when you consume coolant and no obvious leaks then it is a head gasket issue and the coolant is getting burnt up in combustion or contaminating the engine oil..

Good luck:
Marc

Thanks, I have checked the Oil and it seems fine, I keep the oil changed regular, the only Coolent smell comes from the engine compartment.

you could pull the plugs and see what they look like, that may help the diagnosis.

Marc

Our 1999 Aurora looses colent, not a lot, not even enough to see leakage on the ground. I have replaced all hoses and flushed the Radiator. There is no leakage I can find on the inside like it might be a heater core. I am stumped. I have to top off resavore about once a week.

Do you have the pellets in there ? That is supposed to stop small leaks. It could be the bearings or seal in the inside of the water pump. It gets pretty hot, so if its a slow leak, it might just burn the coolant before it has time to drip ? Have it leak checked, that should be so expensive. That might tell you something.

Take a real close look at the plastic radiator tanks (on the sides of the radiator, not the overflow tank) for hairline cracks. Especially around the tranny cooling lines (and engine oil cooler lines on the passenger side tank, if so equipped). I smelled the coolant, too, with no dripping. Thought it was the water pump again, 'till I got a flashlight and stuck my head in there to see the evidence of seepage from a thin crack. Wouldn't drip when sitting. I think it expanded while the system was being pumped up at speed and the leakage occurred while moving.
It is my belief that a cracked rad. tank is the most common start which leads to the overheating that commonly causes the Northstar headgasket issue. Got my mom in her 1999 80k mile Caddy Concours Deville; rad. cracked, low coolant, overheat, dealer says one side headgasket bad. Check those radiator side tanks closely.

Check the 4 gaskets between the water pump housing and the block. These deteriorate and cause slight leak. If this is the problem you will see small coolant droppings under car after being parked over night. Starts real small and get bigger and bigger

My 97 Aurora has the same problem. I might go a month or so and have no problem then it will leak and I have to fill it frequently. I'm getting really frustrated over this. Did you find your problem? Would love to know if you did.

My 97 Aurora has the same problem. I might go a month or so and have no problem then it will leak and I have to fill it frequently. I'm getting really frustrated over this. Did you find your problem? Would love to know if you did.

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