Why does my Van overheat when running idle?
When I run the A/C then park my van, it slowly starts to overheat. I see the temperature gauge go from the middle to hot. The air coming out of the vent also goes from cold to warm. When I put the van back in motion, it cools down and goes back to normal. Any ideas as to what is going on?
Your fan is most likely not working. Check to see if the fan comes on when the engine gets up to temp. If not things to check are fan relay fan fuse and wiring and the fan itself.
Why would the vents pump out cold air when the van is driving if the fan was not working? Is there a corolation there?
There are electrically operated radiator cooling fans to cool the radiator. If they don't come on, your van will overheat when it is not moving forward, to cause cool air to be forced through the radiator.
We are talking about two different fans. The fan that cools the engine (cooling fan) and the fan that cools or warms the interior (blower motor). The cooling fan is the one I was referring to this one is thermostatically controlled. When the engine gets up to temp the cooling fan kicks in. The fan you are referring to is the one that controls interior temp. This one runs depending on user input.
I have the same problem but I do notice that both engine fans are on when its hot.
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