Heater Matrix

[Tim Jones]

Hi All,

I’ve had my 2009 E89 23i into an Independent BMW garage today as my heater is only blowing out slightly warm air instead of hot.

It was checked over and no codes were showing, apart from one for the AUC sensor and the coolant reached the right temperature according to the diagnostics.

Thoughts are it’s a gunked up heater matrix and to get to that it’s a dash out job!!

Anybody know of any way to flush through the heater matrix without removing the dash or any thoughts on anything else it could be causing this issue?

Any help will be greatly appreciated.

Thanks.

Tim

 

[AntStark]

Air lock ? When did you last get the coolant changed?

 

[Tim Jones]

Air lock ? When did you last get the coolant changed?

Hi,

Thanks for the response.

The coolant hasn’t been changed recently so no reason for it to have an air lock I presume.

 

[t-tony]

I would get one of those infra red contactless thermometers and check the temp of every bit of the cooling system you can see, to make sue its all the same temp.
if they are I suspect the thermostat is faulty.

Tony.

 

[colb]

Flush with hosepipe through the hose feeding into the car on the rear bulkhead and let it flow through the return hose flush it both ways. You will have course have to refill and bleed the system when you put it all back together. When flushing just see what the flow is like to judge if it's blocked restricted.

 

[B21]

I’m surprised as to why a heater matrix should gunk up on an E89 if it’s had the correct coolant in it ?

 

[colb]

I was wondering that, could it be a blend door motor gone bad and stuck closed?

 

[Tim Jones]

I was wondering that, could it be a blend door motor gone bad and stuck closed?

Wouldn’t this show up as a fault code though?

 

[B21]

I was wondering that, could it be a blend door motor gone bad and stuck closed?

After the debacles of corrosion caused by wrong combos of metals and coolant in the past I would have thought crap in the coolant system was v unlikely?..unless the wrong coolant was used..with cars this age who knows who cheaped out?