I have a 1998 Eclipse RS. Today I noticed that its been overheating, and all the sudden antifreeze was pouring from the bottom of the car. The A/C also wouldn't come on. I turned the car off, and after it cooled a little I turn it on, and A/C worked again. The car was extremely hot, and you could hear boiling. I took off the radiator cap after it cooled, and it had lots of sludge over it, I cleaned the cap, and put back on, but the car is still over heating.The temp gauge goes up when idle, and goes down when accelerating....Could this be the cap?

 

Sounds like a cracked radiator.

Fill it up with water and run the car at idle, then try and find the leak.
Radiators are an easy fix, right there with brakes.

 

Just replaced the cap, no luck still over heating...Whats interesting is that the reservior is full, and not losing coolant. Is something blocked somewhere?

 

did you find out where it was leaking from or it was just overflowing from the reservior? maybe you have a bad thermostat...my rs had a bad thermostat and it did pretty much the same thing. look into that.

 

I replaced the radiator, I checked the radiator with garden hose and water and it had a leak in it. I refilled new radiatorwith coolant, and started engine, and temp gauge is back to normal, however two questions:

1) The top radiator hose, and the top of radiatoris very hot, is this normal????
2) The new radiator I bought from autozone has 2 extra valve looking brass connectors for some kind of tubes in the bottom of the radiator. Anyone know what these were for? Because they were not on the original radiator, however they don't seem to be leaking.

 

1.) yes that is normal. its cooling down your engine, which means its taking heat from it. and since your engine gets very hot, your hoses and radiator are going to get very hot. (hot enough to boil the coolant, which is why you are not supposed to open the cap when its hot)
2.) if they dont leak, then dont worry about it