Hoot owl whistle
Grrrrr...this stupid thing has started with a faint whistle. Some days yes, some days no. Only hear it in park and neutral. Never while driving, does not change with RPMs either. Just had a 160,000 mile full service, dealer says all belts, fluids, etc are in perfect condition. Does not make sound on start up. Seems to only happen after driving for a while and things get "warmed up". No indicator lights on display. No leaks that I can tell. Slow, steady whistle, sounds more like an owl hooting. But, as soon as I turn the car off, then you can really hear the hooting for about a second and then done. Any ideas?
Check your crankcase vent and or PCV valve, might be blocked. Also check all the hoses too.
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