Heater working intermittently-any ideas please?

Hi there, my dad has a 200 tdi and his heater works fine/hot...then goes cold...and after a couple of miles starts working fine again. He has heard it could be either the water pump or the matrix? Does anyone have any ideas on this please?
Many thanks in advance!!

sounds like an air lock , or your cables come off the top so the internal flap is going where it wants to .

Hi and thnaks for that! Please could you just explain a bit more about what you mean about the 'internal flap'?
Really appreciate your help on this!!

You have a cable that goes to the top of the heater yeah ? - conects onto tis arm circled in the pic . if its free to move on its own ( loosely ) then it'll move about directing the air either through the matrix or around it internally .




Its a possibility if you have no air trapped in the matrix . how hot are your pipes after youve given it a run to warm it up ???


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yeah i dont think its a major problem i doubt its the water pump if the pump was shot you would have now heating at all and after a run you would probably have the engine over heating i doubt its the matrix either are you losseing coolant if its a disco the matrix is in the dash.. so you would notice a wet passanger floor which would mean a dash strip out job to repair. take syphers advice first then start looking else where

Half asleep when I did that post before , I automaticly thought it was a 90 .

Is it s 90 ? - or is it a Disco ?


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