Hi everyone, this is my first time here. I have a 1998 Civic Ex that overheats with the arrow at 3/4 of the way (at least) while idle, and dips down back to normal while moving. The arrow on the gauge will start to rise after 30 minutes of driving or so. When it gets to 3/4, I stop the car. This only started happening after I came home from the hospital a few months ago. It wasn't being used much due to me being in the hospital off and on for a year.

So this is a worrisome change to me. I took it to a local auto shop today, saying I thought maybe a fuse needed replacing, as the cooling fan was replaced about a year ago, there's plenty of coolant (no leaks), and two separate people said my fan didn't seem to be coming on. The mechanic called an hour later and said the car seems fine, that the fan does kick on 3/4 of the way at about 200 degrees, and that was normal. He charged me $45 for this, and originally said $90 (which enraged me).

I don't think this is normal at all, and I want to know what else may be wrong with the car. Any ideas? My dad said he's going to check the fuses and see if the fan will turn on. Oh and the radiator was replaced five years ago.

 

The fan is controlled by the temperature of the coolant leaving the radiator, not the engine itself. It should come on when that temperature reaches 160 degrees, which is long before the engine temperature needle starts to move up. The engine runs at 185 and should stay the same throughought different driving conditions.

I suggest you unplug the fan switch and jumper it so the fan runs all the time the key is on. Test drive like that and if there is no overheating, replace the switch. Some people have had problems with third-party parts supplier switches instead of original Honda.

The fan switch is located on the thermostat housing, where the big hose from the bottom of the radiator attaches to the engine near the starter. (Unlike most American cars, the thermostat is in the bottom hose instead of the top one.)

You should also when the engine is cold, take off the radiator cap and confirm the radiator is full to the top. Having a pocket of air in the radiator and engine will cause poor cooling.

 

^That and get a new mechanic. Doesn't seem like he is willing to actually diagnose the problem. I work with cooling systems on a daily basis.