I have a 1999 S80 T6 and in the past few months it has developed a cold starting problem. The car almost starts on the the first turn of the key but then stalls. Upon the second try the car always starts. This problem only happens when the car sits for a long period of time (4 or more hours). I have had the car at the Volvo shop 10 times in the last 30 days. They seem to be baffled at what could be causing this problem. It's not that they lack experience or the willingness to fix the issue I think that they are honestly stumped. They claim that they have seen this problem before but it was solved by replacing the parts they have already replaced on mine. So far they have replaced the throttle module, fuel pump, and most injectors. Can anyone offer any suggestions or possible fixes?