| For what it is worth I have a '97 740il. About 2 years ago with about 65K on the odometer it began a subtle miss almost exclusively during warm up idle. Initially it would clear within 3-4 minutes. Felt like a mildly fouled single plug but was irratic occurence wise, not always happening. Gradually occurences became more noticable but still subtle, not enough to really stop and go after. Always at idle and never above 1000 rpm it finally set the check engine light. Took it to the dealer and was the convertors. Funny thing was even at the end it was not every time you started it and almost imperceptable when warmed up. | 
