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2005 BMW X5 Question: My BMW X5 has around 85k in it and blue smoke coming out on the tailpipe

 

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kalman, 4.4L V8, Romulus, MI, September 11, 2011, 18:48
 Rookie

When I push the accelerator pedal to the floor.After 30min. of engine running the smoke is a little less but it's there.My question is:- PCV valves or valve seals or what else could be the problem.

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    patrick mannion from Greg Solow's Engine Room, September 11, 2011, 19:34
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     Master

    Is the engine requiring oil between services? It is normal for an engine to require a little engine oil between services. For an engine to require excessive amounts of engine oil between services means the engine is either burning oil or leaking oil. Leaking oil should be pretty obvious, look for leaks underneath the engine at the oil filter, oil drain plug, and oil filter. Look for oil leaking from the timing belt cover area/timing chain cover and valve cover gasket. If an engine is "burning oil" look at the tail pipe and rear bumper for signs off discoloration or black oily deposits oil. Oil may leak down the valve guides particularly after the engine has been shut off and started from cold,if so blue oil smoke may be emitted from the tail pipe on start up, (this may also be noticeable if the car is left idle for a few minutes and then accelerated away for example after sitting at a traffic light). If the piston oil control rings are worn the engine normally smokes on acceleration. Oil control rings may fail due to an engine that has badly overheated or has had infrequent engine oil changes. Frequent oil changes with good quality oil is critical to long engine life. Perhaps changing oil viscocity to the next "thicker" grade would help.

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    kalman, September 12, 2011, 04:16
     Rookie

    No oil leaks from the engine and no blue smoke on start up just after couple min.of running and also when the car is left idle for a few min.and accelerated away.When the car been used for amount of time it's less blue smoke and almost nothing when it's accelerated away.Why it's that

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    Baviel, October 07, 2011, 06:58
     Rookie

    I have exact same problem with my 04 X5 4.4. Starting in the morning with no smoke what-so-ever, but after waiting at traffic lights or stop signs, blue smoke coming out when accelerating.
    No oil leakage found, changed the breather valves problem still persists. Can it be breather hose clogged? From reading the diagrams from realoem.com, it's pretty complicated to change the hoses under cylinder covers, does anyone figure out what the cause maybe, and done a breather hose change, DIY with pix?
    Thanks!!!!

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