Overheating

[skimmilk]

I have a 1994 540i with about 125,000 miles on it. Lately it has overheated. About two months ago was the first time. I noticed that the temp. was going up and I shut it off and started it back up again about 10 minutes later and no problem. I drove it for about two months with no problems. then a week ago it overheated again but i didn't catch it and steam started pouring out my vents. I then waited untill the next day and drove it for another week with no problem except for my windshield would always have condensation on it. Then last night it started to overheat again but I caught it. I dont know what is the problem with it especially since it has appeared to go away. My friend thinks it's the heater core. My dad tells me it could be the thermostat. Some other information that may be helpful is that everytime it has overheated the car has been idleing with the heat on full blast for long periods of time, probably at least an hour. It also was leaking coolant a bit when it overheated the one time but it stopped leaking. It seemed that it was leaking from a place where there is like three hoses going to it but it wasn't leaking much at all. I dont know too much about cars If anyone could help me out i'd appreciate it. thanks
willy

[lensbud]

I had simillar problems with a 2000 528i, very intermittnet overheating. I took it to my mechanic and had the thermostat replaced no problems since. Len

[billB]

While foggy winshields is heater core I would start by checking the heater hoses going into your firewall. They do crack due to intense heat/age, also check those little clamps over them.

good luck