parker455

Hi there, Sorry for my late response I've been working on this in the background. So I had the dash apart and looks like the heater control flaps in the matrix are working, when AC is on the flaps function and without AC the flaps function from hot/cold. This would indicate that the matrix itself is blocked OR the control flap itself has actually snapped i.e flap inside matrix isn't opening but I think this is unlikely.. Next step for me is a full coolant flush and I'm going to try and push fluid back through the matrix in the other direction. I need to get a cambelt/waterpump changed in the next thousand miles or so, so I think I will be checking how pressured the system is via the waterpump as if this is damaged (shouldn't be, but never know) then it wont pressurise enough to push through the matrix. I'm thinking out loud here but might be totally wrong. It's getting cold so I need to get this sorted next weekend.

Afternoon, Gareth. Thanks for your response it's much appreciated. So today I've had the car up to temp, heaters blowing on Hi (dual control but both set to hi) and have been squeezing all of the hozes I can get my hands on for the heating. Seems like this lower hose line is still dead cold so my thoughts are a heater valve behind this OR the core is blocked. There's been some talk online of the cores being blocked and I can't find any evidence of a coolant flush on this so it's possible. I bought the car through work and it came from a VW authorised dealer around Feb 2015 at 6 months old so I would assume it may still have some warranty but I'm not too sure I will have to check paperwork. I'm unfamiliar with the heating systems in these but have worked largely on 90's jap cars which are somewhat alot simpler. Is anyone aware of the solenoid that controls the heating? To me everything is pointing toward this core being blocked OR the valve control (if any?!). The thought of the backflush would be to see if anything is passing through the system, which currently it seems like it's not. Other option would be to leave the hot (in) feed and disconnect the line thats running cool and see if coolant passes through. I'm looking to do a full change on this anyway along with cambelt/waterpump so it could be a good time to address it. Any thoughts would be really helpful! Many thanks, Tom

Hi all, I'm trying to diagnose why I've got no heating in an A3 2014 8V. All my temps seem to be fine and we're not overheating at all. I don't have VCDS so this makes it slightly more difficult however.. I have located the what I presume to be the in/out feed into the heater matrix. The top hose feeding into this gets hot and I would assume this is the in, however the lower feed remains consistently cold even when up to temp. I am assuming the heater matrix is blocked, however is there a solenoid or valve behind this at all that could be stuck? My other way of trying to clear this blockage was to maybe disconnect the lines and pump fresh water through the matrix to try and clear any blockages from both ways. Thoughts? The heating hasn't worked in around a year and i'm sitting at 110k miles so it's due a full coolant flush any minute anyway. Any help much appreciated!