Originally Posted by Electron-Jack
Can someone tell me what actually fails on the phaser. I'm in the middle of a rebuild and after inspecting mine the spring is still strong adn not broken. The phaser is not bound up inside the cam gear and will still rotate with enough force applied to overcome the spring tension. So I don't see what else could be wrong. So anybody whose actually seen a bad phaser I would like to know where the mechanical failure occured. I read so many articles on here syaing they replaced phasers and still had the same noise afterwards. I think in alot of cases its the cam followers and lifters that fail like the one I bought with 173k on it. It was knocking a little and when I got into it, it had a bad lifter and cam follower roller.
Mine were the old version with roll pins that held the phaser together. On my driver's side, two of the pins were missing and it just fell apart in my hands once it was unbolted. The passenger side looked fine but it was the more noisy side. That was due to some extent to a bad solenoid but not entirely. There's not much inside of the phasers to fail - just a series of chambers which are filled with oil depending on the solenoid.
I'd agree that a lot of the complaints about noise and problems attributed to the phasers themselves actually are lifters/rollers, bad solenoids, oil flow or pressure-related, chain/tensioners, etc. Most people are pretty bad as far as being able to distinguish various engine noises but if you know what to listen for in most of them you can clearly hear the lifters clacking and the chain singing independent of anything going on with the phasers. Probably 1/4 of my lifters were pretty much beat. Solenoid on the passenger side was done. As above, driver's side phaser was mechanically busted. Overall, I'm not real impressed with the whole variable cam system used in these motors.