Here's an odd one, once the cars warmed up it blows hot air fine however after a while it will suddenly stop as if the climate control has decided to run cold instead despite the slider being all the way to the red, any ideas? im thinking a fault with the panel that's closing the mixer door or something :S /shrug
Weird heat issue
- Thread starter ubersonic
- Start date
Sounds like your bvsv is leaking....the valve on the firewall on the passenger side that controls the coolant flow to the heater core....wire open and see if the changes anything.
I had the same problem and it turned out my heater core had a couple of pinhole leaks. I water pressure tested it when it was out of the car and it was misting and spraying. It takes a while to remove it from the car but I bet that you could test it while still in the car. Just use the hoses on the firewall under the hood. Disconnect each side and cap one side with something. And with the other side find all the plumbing fittings to hood up a garden hose. And stick a pressure gauge on there. Fill it with water and leave it. See if the pressure gauge drops and you will know if there is a leak.
When it goes cold if you cycle the heater slider max to min can you hear the mixer door servo moving?
Just another idea from what just happened to me....I needed more antifreeze in my system as it had lots of air. Once I added more fluid my heat came back as a constant. I had sporatic heat and cold air blowing...
cwd
cwd
IJ.;1795321 said:
No, im not sure exactly what that's supposed to sound like but once its stopped being hot and just blows cold then sliding from left to right makes no noise. Also im *pretty* sure that I hear that noise just before the heat goes off.
When I start the car in the morning the heat comes on fine once the cars warmed up, however if I turn it off and back on again it will just blow cold and this persists until the next day when the cars been standing all night and works again the once. If I carry on driving after the cars first started and blowing hot then eventually it will just go cold (im sure im hearing a servo doing something when it stops) and the change is very rapid, i.e on full heat it will go from boiling air to ice air rapidly. Its difficult to explain but it doesn't feel like the heat dies off (like my radiators do in my house when the central heating turns off), more the heat is diverted away like turning a tap from hot to cold.
Zip tie the heater valve up and see if it goes away. That will easily eliminate that component and you can get on to the next.
Make sure coolant is full too.
Make sure coolant is full too.
Zip tie the heater valve up and see if it goes away. That will easily eliminate that component and you can get on to the next.
Make sure coolant is full too.
Make sure coolant is full too.
Look above the dashboard on the passenger side, it is a sensor that has a piece of dark color glass on it. If you leave the heater setting at 85, the maximum, does it work? The lowest and highest settings on the climate control are supposed to bypass the sensor.
O, I am not sure if you have the sensor. Check and see first. If its there, it should bypass it setting it to the lowest or highest setting.
it's the solders on the climate control board.
I have a jdm mk3 and I had exactly this problem. I'm trying to find the website that explain this with pictures but I'm not able.
You only have to remove the climate control, check the connector at the back and inspect all solders. You will see small cracks. Resolder and it will be ok.
I have a jdm mk3 and I had exactly this problem. I'm trying to find the website that explain this with pictures but I'm not able.
You only have to remove the climate control, check the connector at the back and inspect all solders. You will see small cracks. Resolder and it will be ok.
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