Markymidnite

Hey guys.. I have an 03 audi a4 quattro 1.8 and I'm having trouble figuring this out...bought the car top end has been all redone...was getting p0172 fuel bank 1 rich... I replaced evap and 02 sensor as well as cleaned maf... Seems to have taken care of the cel....Car runs super solid and no rough idle or any problems..except after a long idle and it's warm I start getting smoke out the exhaust... Pretty sure it's oil it's white w a little blue color...Definitely not black... As soon as I drive it crop dusts for a second then goes away and is fine...what could this be? When it does smoke the idle is not affected stays perfect...and Normal driving it doesn't happen...only after like 5 min or so of continuous idle... Pcv maybe? all the hoses look fine but I couldn't locate the valve location...I got a turbo boost control valve haven't got it in the mail yet...I duno if that will help but I'm lost on where to go from here
Thanks in advance for your thoughts 😄

lyleswk

Blue smoke in exhaust means your burning oil and on a turbo car usually means it's the turbo. Know any maintenance history on it before you got it?

Markymidnite

I have replaced all the pcv valves and checked all hoses.. no oil on spark plugs so i dont think its valve seals.. a BIG thing i just noticed... the car does not smoke when the A/C is ON....
i let it idle for 10 min and nothing and as soon as i turned the AC OFF it started smoking from the exhaust... i was thinking it was turbo seals but this seems to be some kind of ventilation issue or? anybody have any ideas on this?? thanks

lyleswk

My experience with a clogged PCV system is it burns oil over tiime, but not in a quantity that would create noticeable blue smoke. Maybe some others have a different experience.

WeekendDriver

I have just recently come across a test where you idle for a while and then step on the gas and watch the exhaust. If you do indeed see the smoke in this case but not when running at higher RPM, it indicates the problem with the valves, but I can't recall specifically which part. I'll try to find that post for the details.