You MAY be meaning on top of the transmission bellhousing. That would be the coolant temp. sending unit or the coolant outlet return hose to the radiator or the O-ring that is on the black plastic adapter that is mounted to the head by two screws. Anyway, get one of those mirrors on a stick, and look underneeth that black part and hose and sending unit for signs of coolant loss. If there is...simply remove the leaking part and tape the threads or replace the sender, repair the hose or tighten the clamp or remove the two screws and twist back and forth while pulling strait out on the black plastic adapter. Then replace the O-ring. Be sure to "BURP" the coolant system when refilling the coolant. To burp the thing,leave the cap off while letting it get to operating temp. .... It may help to have the car on a SLIGHT slanted surface with the driver side being higher than the passenger side so the air in the head can leave the head easier.
The coolant level sensor is faulty.
1995-2004 2.4 engines (Z24s & Sunfire GTs) have a metal coolant outlet line on the firewall side of the engine block. The thermostat housing is an intergal part of this outlet line as well. This would be the first place I'd check for a coolant leak between the firewall and engine. Good luck.
This depends on where the leak is. A hose could be loose or broken or there could be a radiator or engine leak. The area of the leak needs to be found to be able to diagnose.
If it is the low coolant light, it may mean your coolant is low. If it is not low, it may be the low coolant light sensor malfunctioning.
A bad head gasket , a warped head usually from overheating , would allow engine coolant into an engine cylinder
The normal direction of circulation in the coolant system would push the coolant out the thermostat opening.
There is a sensor on most modern cars which turns on the fan when the coolant temperature reaches a certain value. If this sensor is bad, the fan may run continously.
Check your overflow bottle to make sure there is adequate coolant in there. If there is, the coolant level sensor is faulty and must be replaced.
Yes, it controls the coolant flow around the engine block, without coolant the engine would overheat.
Low coolant would be because the coolant is low or the sensor has failed, Check engine light would be because the computer has detected a problem and set a code.
Engine rod? Engine bearing?
That would be the engine coolant temp sensor for the dash gauge only. The sensor near the thermostat housing is the engine temp sensor for the ECM.