My BOV worked fine for a while. I haven't touched the settings or anything. But recently, I noticed that on cold days, the BOV doesn't make the smooth "ChhhooooF" sound that it always makes. Instead its like "chhhhh.................ooofffffFF". There is like a big delay and its nto even loud at all. And after like an hour of driving, the sound is normal again.

Any idea why it does that??

 

Like the Tin Man in The Wizard of Oz said....

Oil...... Can.....