Hello. I have posted a few things before about my poor S5 that suffers from sporadic overheats... I am pretty sure that it can be attributed to blown coolant seals casue it sure burns coolant! Anyway, last time I noticed the heat jump up, I turned on the heater and the fan full blast, and the air coming out was not hot, just normal air.... any idea why that might be happening? could I have a colossal clog or some such thing somewhere that might be causing some overheating woes? Conversley, my A/C isnt working either, but I think thats becasue the belt is slipping on the compressor, I dont know if the two problems are related though.
Its very strange becacsue sometimes the car doesnt ovehreat, runs fine, and the heater actually blows quite hot... help?

 

Logicon failure or air mix motor failure are more common when the heater is not changing temps, but I would not rule out that the cooling system is not working correctly.

When was the last time you flushed the system?

How much coolent are you loosing and is it just into the motor or could it be leaking out the water pump?

 

well , when u are out of coolant, therefore heat can't be transfered, and that's why when u turn on the heater and fan at full blast, no hot air will come out, my guess is u are at or almost at the stage of overheating ur engine when u noticed that no hot air are coming out when heater is on

keep ur eyes on the coolant level of the radiator, maybe every 1 or 2 days, it should be ok

and yeah, get a rebuilt dude, in the mean while for now, just make sure u don't smoke ur engine and burn everything under ur hood, could cause some serious money in rebuilting and etc

good luck

 

you need to pressure test the cooling system and find out where you have a leak. If you have a leak at the engine block, its game over for that motor. You could just have a bad cap or heater core.

 

Do a search for the Paul Yaw temporary fix for engine cooant seals, it could buy you some time to save up for a new motor.

Should give you a few months.