How does this system work

Refer to TSB 02-157-14R, and pay close attention to page 16. It refers to the importance of preloading the timing chain tensioners during assembly. Not performing this step can cause exactly the symptoms you've mentioned.

Great tip! I just checked STIS to see if the service manual had the same instructions. It didn't. Gotta check for TSBs I guess. Subaru actually has some really great service information, but it's not always found the service manual. A lot of times you'll only find what you need in the Technician Reference Booklets and TSBs.

Thanks for that heads up. I try to look for tsb's when I do any timing chain work. I would have seen this tsb, concerning engine oil comsumption, and I would have looked past it.

I agree with Leo about preloading the tensioners. These chains will rattle unless you got that extra click out of the tensioners after pulling the grenade pin.

I'm not 100% sure about your exact engine, but most of the Subaru VVT sprockets I've played with have a spring-loaded lock pin that prevents movement until oil pressure releases it. That said, it looks like Leo probably solved your issue.

The tsb mentioned doesn't come up in Alldata, it states it was superceded, the superceded one isn't available, what I did last night was manually activated the solenoids I can hear them click, then I started the engine and activated them a few times. This morning there was no noise. Did it the tensioner get the extra click or the phaser was sticking? I'll keep trying the cold start to verify…

Hi Fred, Here's a copy from STIS. Although I did see it in Alldata as well (see screen cap).

Thank you, its odd I did a tsb search and the tsb didn't come up, but went I scroll down the tsb list it does, its under oil consumption. Thanks again