Originally Posted by
svtmerc
I had a little nugget of stumbling this morning on the drive in to work.
In my endless pondering, a question popped in my mind... I have some oil leakage due to the oil level sensor not sealing completely. Is it possible that negative crankcase pressure is pulling in unmetered outside air and pulled in the intake via the pcv system causing the lean codes and intermittent rough running?
Good question, I guess it might be possible. To see if that is a possibility find all the hoses for the PCV system that returns to the intake and plug both sides of the hose or hoses you find (I believe there is only one that goes into the elbow before the throttle body or the TB itself?). Maybe other members know if this is a certainty? Make sure you plug both sides (the hose end and the elbow end) of any/each hose you open up. Good luck!
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