Evening chaps, I purchased a 2004 BMW E46 318i touring today. I've spent all week looking at coupes and saloons which were in all sorts of states. At one of the last ones today, I loaded up Autotrader to see what else was nearby and up came this touring a few miles away, figured I had nothing to lose by checking it out. Anyway, all looked good - clean arches, 4 decent premium tyres, FSH, 11 months MOT, xenons, bluetooth etc. 108k on a 53 plate. Wasn't my original choice but it's only going to be a work hack. Paid £1800 with the garage agreeing to do an oil service (showing 3k left on the dash). Drove fine on the (short) test drive, thought it was surprisingly smooth and quiet for a 4 cylinder (also have a 3.0 z4 with the m54). Didn't notice any smoke but I was on fairly busy unfamiliar roads and focusing more on that. Driving home I noticed the occasional puff of blue smoke when setting off after idling. My Dad was following and he said although it wasn't often, when it happened it was obvious. I'm actually in the process of getting rid of my old Focus due to worn piston rings so blue smoke was the last thing I wanted to see! It doesn't smoke upon startup, or idling, just when pulling away in first gear and very occasional in gear under load - and not all the time either. Is this likely to be the piston rings / worn stem valve seals or could it be something like the PCV / oil breather pipes? Initially thought of ringing the garage up on Monday and handing it straight back. I'd like to take it to my usual BMW indie and get his opinion but reluctant to fork out any money if it's going back.