Everything runs fine, A/C is good, idles and runs strong.

But ....

The heater was turned on tonight in the car and the cars temperature gauge went way to high almost to the H until we turned on the cooling system which lowered the temperature.

Any ideas on what hose is mixed up? Havent had any time to fix it yet.

THanks.

 

It's possible coolant was changed awhile ago, and a air pocket was in the heater core. when you turned on the heater the air went to the engine, most likely the thermostat.

Or you've got a coolant leak somewhere and it's low on coolant.

 

How about some background. What have you done to the cooling system that you even think hoses could be "mixed up"? Just posting a problem and having us guess without telling the background is unproductive.

 

I'm guessing because reinstalled an engine in the vehicle.

 

Yea I can't give any more background than that. (just installed engine)

I will flush the coolant system this afternoon since I'm getting word that this might be the problem.

The thermostat works fine by the way.

 

Does anyone think the car is unsafe to drive?

The car looks like it cools fine and the temperature gauge is always at 3 bars its only when I turn the heater on.

Thanks.

 

Ok here is what happened:

After the install the car ran fine and so did the coolant system.

It recently turned cold here and I turned the heater on while driving the car's temperature ran up real high and wanted to overheat so I pulled over and let the car cool down by turning the A/C system on which worked.

The Resevoir tank was overflowing and shot fluid out from the tank.

It's as if the fluid isn't flowing properly somehow or another when the heat is on.