i want to know what could cause bluish grey smoke to all of sudden come billowing out of the both exhaust pipes at the same time after riding in the car for about 3or 4 miles and 10 or so minutes of operation?
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2003 BMW X5 Question: smoke from exhaust pipes
Answer #1patrick mannion from Greg Solow's Engine Room, February 11, 2009, 22:26Master
Blueish grey smoke from the tail pipe is oil smoke (black smoke from the exhaust is usually excess fuel, white steam from the exhaust is usually due to a blown head gasket).
Oil smoke from the exhaust means oil is entering the combustion chamber and being burned in the cylinder before being expelled out the exhaust. Oil can enter the combustion chamber due to a damaged or worn oil control ring on the pistons, or worn valve guides or worn valve guide seals. Before assuming the worst check the engine oil level, could it be overfilled? Get a friend to follow you on the freeway, on steady acceleration does blue grey smoke bellow out of the exhaust? That would be a sign of worn rings. If you get clouds of blue grey smoke when you first start the engine or after the engine has idled for several minutes and then is accelerated that may be a sign of worn valve guides or worn valve guide seals. Do you smell a burning oil smell or have blue grey oil deposits on the rear bumper. Get it checked as soon as possible. If you do indeed have engine damage its best to attend to it as soon as possible.
Answer #2Visitor, March 11, 2010, 10:20
smoke when acclerate
Visitor, March 30, 2010, 07:17
I have had several cyclone seperators go bad and cause this problem. You need to check your vacuum, with a water/vac gauge, if the vacuum is low the seperator or hoses could be clogged or the seperator could be busted on the inside.
Answer #4robhart80 June 05, 2010, 04:48Enthusiast
I had this exact problem, it was a differnt car though! It was a turbo 300 z! It was horrible but wouldn't do it in the driveway, it waited 'till I got into town and stopped at a stop light! I freaked and spent a fotune replacing the turbo, all the vaccum lines, redid the heads, and so on. After almost 4500 bucks in parts and 3200 in labor I got it back, got to the first light and blam, I couldn't see the car behind me! It turned out to be the PCV VALVE!!!! A freakin' $3 part! Hope it helps! good luck!