1995 Honda Accord LX Station Wagon. 4 cylinder. Manual Transmission. 200k on the odometer. Well cared for although it's probably due for a timing belt change. In doing some running around yesterday, including some highway driving. I noticed my car running a bit on the hot side. The coolant level is low in the overflow tank so I intend to top that off. I'm a right in thinking that these cars require a different type of coolant than the green stuff? When I'm moving along the temp gauge hovers just below the halfway point, which is higher than it has run in the past. When I'm idling the temp gauge creeps up past the halfway mark. At one of my destinations after a hard drive up a long grade, I made a 3 point turn to position my car in a driveway facing towards the road. The temp gauge crept dangerously high. I noticed that hot engine smell. Shut the engine off and one of the two electric fans associated with the radiator was engaged (passenger side). I let the car sit for a bit while we visited with friends. On the trip back home is when I was really paying attention to the temp gauge and noticing the fluctuations when traveling and when idling. Upon arrival; this is were the temp gauge sat after idling the car for a few minutes. Let the car sit overnight and haven't driven it since. This morning I ran my car for about 20 minutes with the hood up and the temp gauge never got past where it normally runs at. Inspecting the engine I did notice that a small hose had worked it's way loose from the head cover. There was air coming out of the head cover where the hose would normally be attached. The hose runs from the air filter tube to the head cover. I've put the hose back on but haven't taken the car on a test drive as of yet. I'm waiting for my wife to come back home with the debit card before heading to NAPA to get some coolant. Perhaps that hose being off was dumping hot air into the engine bay and causing the engine to run abnormally hot? What is that hose for? I had initially intended to take the car into a Honda Specific mechanic (he get's all my business when it comes to repairs for the Honda, highly competent, excellent customer service, doesn't gouge you on labor). Is it worth taking it in?