Hi every one this is my first enquiry, I think this may have been asked before, car purchased May this year 96,000 mls on clock, weather has got colder heater not good. I have flushed several times but not got any better, in fact bloody cold. Can any one recommend a good flushing agent I can purchase, I think I heard of one that may have been acid type. Car has been used for towing caravan 1500 kg and does it great. Now covered 104,000 mls. Any help would be great. Mike P