If it had no leaks it would not be loosing coolant. So therefore it does have a leak. It can be leaking in a spot where the coolant burns away before dripping on the ground. Also a blown head gasket is a possibility. Look for coolant in the oil. A heater core can leak. Do you smell coolant inside the car or are the windows fogging up or developing a film. You need to have a pressure test run on the cooling system and find this leak.
If the electric fans do not turn on by the radiator ...if the thermostat is stuck closed...low coolant level...bad head gasket...clogged radiator...clogged exhaust pipe or catalitic converter..... All can cause overheating.
Several possibilities - from easiest to most expensive: Faulty or inoperable radiator cooling fan - causing overheating. Faulty thermostat - causing overheating. Water pump failure - causing overheating. Blown head gasket - allowing exhaust gasses to escape into the cooling system and expelling the coolant.
Bad head gasket or... Crack in exhaust port in head. Check exhaust for presence of antifreeze smell or exhaust gas in radiator.
Is "all new coolant parts" everything? Thermostat is the first thing. Is the cooling fan coming on? New radiator cap? If everything is in fact new, take the cap off and start the car to see if the radiator is being pressurized with exhaust. A bad head gasket, cracked head or block could be the problem. Starting it with the cap off will cause coolant to blow out of the radiator.
You should the head gasket. If you go to Autozone, they have a tool that can check for exhaust gas in the coolant which may tell you if you have blown head gasket. Also, check your oil to see if it is milky or if you are blowing white smoke from the exhaust pipes. HTH
On many engines you have to bleed the air from a bleed screw or trapped air will stop coolant from circulating. Thermostat installed backwards? Radiator plugged up? Hopefully it's not head gaskets. If it's blowing white smoke and the exhaust smells sweet, then it is head gasket.
If there is no overheating or loss of coolant, most likely it is due to condensation in the exhaust system (pretty normal in cool or rainy weather).
if it is a four cyl it is most likely under the passenger side of the engine at the end of the bottom radiator hose it is best to take of the exhaust manifold to replace it is possible that it can overheating if it it bad I have a 1996 Grand Am SE, and mine runs hot too. Its probably not the thermostat, if not, then try flushing the coolant system, or the radiator might be clogged up.
If you have odors coming from the engine area you probably have something leaking be it oil, engine coolant or exhaust. If the engine is overheating, a radiator flush may or may not help because there are several reasons why it could be overheating. Take it to a trusted mechanic for diagnoses.
Removal Procedure:Remove the air cleaner and duct assembly.Drain the coolant until the coolant level is below the thermostat.Remove the crossover exhaust pipe.Remove the radiator hose from the thermostat housing.Remove the thermostat housing bolts and clean any sealer from the bolt threads.Remove the thermostat housing and gasket.Remove the thermostat.Clean the mating surfaces.Installation Procedure: Install the ThermastatInstall the thermostat housing and gasket.Install the thermostat housing bolts. TightenTighten the bolts to 25 NÂ·m (18 lb ft).Install the radiator hose to the thermostat housing.Install the crossover exhaust pipe.Install the air cleaner and duct assembly.Fill the cooling system.
Overheating. Loosing coolant with no apparent leak. White smoke with a sweet smell from the exhaust. Coolant in the oil. A foamy substance on the underside of the oil cap. Air bubbles escaping from the radiator. Engine missing on one or more cylinders. Loss of power.
Overheating is almost always cause by either low coolant level, stuck thermostat, plugged radiator, plugged engine coolant passages, blown head gasket, bad water pump, non running electric cooling fan at radiator, or loose water pump drive belt. Check fluid level, check drive belt for pump, look for leaks at the water pump, turn on A/C and see if fan is running, smell exhaust (sweet smell indicates blown head gasket), start engine when cold and radiator cap off. Look for flow of coolant in radiator. No flow usually indicates a bad water pump, or a stuck thermostat. If all these check OK, then you may need to remove radiator and have it cleaned. Replace the thermostat at this time. Bleed the system after reinstalling radiator and filling with a 50/50 mix of antifreeze and distilled water.