My car has been experiencing a little bit of idle problems of late. The car is a 1998 S80 T6 that has done about 180000km's. The problem seems to be more when the air con kicks in while at stand still (i.e. at the lights). The car exhibits the classic signs of the ETM misbehaving. I have checked my ETM and the sticker is yellow, so hence it means that it has already had the recall done on it. The most recent thing that has been done to the car was the water pump and radiator. There was 1 stage (after the radiator & water pump install) where the oil cap was not sealed correctly (i.e. it was not on fully) on the engine, which caused it to leak some oil and also have erratic idle because of this. I also noticed it's not as bad as it was after I put in 95-octane (premium petrol) in. Any suggestions as to what is going on here? No diagnostics and it's random when it happens (i.e. can be from cold, warm or hot startup).

 

ETM might need to be cleaned.