Trying to find info and not having much luck; my 2012 Mazda5 is making some noise behind the front cover; service advisor (I trust him) said it is the tensioner and guides. No big deal since car is closing on 160k it definitely time for this; however, he also suggested that the cam phaser be changed while we are in there. I can't find anything about this on these so I'm hoping someone knows. I'll have the dealer do it, I don't have time and need to not be working on this when I have so much else to do.
Any input? Timing chain, guide(s), tensioner, "phaser" all at once?
Cam phaser is the gear assembly on the front of the cams that the timing chain spins. I'm not sure why it would need to be changed, though. Maybe ask the adviser why it is suggested?
Right, he said they "fail". I can't find any info on that and was hoping someone had some knowledge.
Might be similar to Toyota's VVTI cam gear that has a rubber gasket inside which fails and causes an oil leak that people mistake as a cam or crank seal. My Lexus has a sticker inside the timing cover that warns not to open the gear as it's balanced from the factory, treat it as non-serviceable and to replace the gear. There are videos on youtube showing how to put it back together correctly. I did mine recently.
I guess the smart money is to replace them. They don't seem TOO expensive, and if you've got a good relationship with the facility, you should be able to talk them down in labor hours since they're going to be in there doing other stuff.
