Have done a search but nothing conclusive. Got a weird problem on my 2002 PD130. When driving along, after the car has heated up, the heaters blow plenty of hot air as you would expect. However when you stop the car, and have it just idling the air gets colder until its blowing cold air! My VAG techie pal thinks it could just be as simple as an air lock in the rad? Im hoping its not the pump, as the previous owner apparntly just changed it! Anyone had a similar problem?