There has been many of threads on this issue. One night I promise you I read 30 of them. It seems the people on this board that really know the mechanics of our vehicles say to replace it or take the chance of your motor eating the valve and then It could be a complete rebuild. Even with the hose disconnected. Have I done it with 119,000 miles? No.... Should I? Popular vote says yes. Then again my trusted Mitzu parts man says he has never heard of one person with this problem. I got the impression he thought I was crazy asking. But then why a new part to replace the old one? Because it is defective. Many sides to this story.