My Explorer is running hot when I'm idle. Is this just a simple case of I need to add coolant? Probably not. I find it odd that it goes back down to the normal range when driving. When the vehicle is moving forward, AIR is forced through the radiator, thereby cooling the engine. When the vehicle is standing with engine idling, the COOLING FAN provides airflow needed to prevent overheating.
It is likely the FAN is the culprit here, or more correctly, the FAN CLUTCH, which drives the fan blade when it "feels" hot air coming in through the radiator.
With the engine hot and idling, at operating temperature, open the hood, and place your hand above and slightly behind the top of the fan shroud. You should feel a distinct blast of hot air, which indicates the fan is drawing air through the radiator. If there is NO obvious heat coming out, the fan clutch is not operating to drive the fan. NOTE!! Do NOT GET YOUR HAND CLOSE ENOUGH TO THE FAN BLADE TO BE INJURED BY IT!
Replace the fan clutch.
BTW, would i need to green coolant or the orange. They asked me that question at Advance. It is a V6 4.0 2WD. Use coolant approved by Ford for your engine. This info is in your Owners Manual. imp
thanks