I have a '99 CSVT with 47k miles. Having seen so many reports about waterpump failure and engine damage, I am planning pre-emptive replacement, but am curious as to exactly the problem. Have heard impeller failure, have also heard loose backing cone causes the problem. If it's the cone, what has to be done to fix? Does impeller material (metal or plastic) really matter. Please clear up the vagueness of the problem
