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Issues with hydraulic cam (left bank, intake)

PostPosted: Thu Jun 02, 2011 9:34 am
by tangcla
Just wondering if anyone else has had issues wit htheir hydraulic cam lift system, in particular their left bank, intake cam.

Mine is suspect faulty and apparently it's a (reluctantly) known issue with the 04-05 Liberty.

Re: Issues with hydraulic cam (left bank, intake)

PostPosted: Thu Jun 02, 2011 11:02 am
by Robbks
Is this the same fault with the oil filters in the AVCS system that affected the WRX's of the same era?

Re: Issues with hydraulic cam (left bank, intake)

PostPosted: Thu Jun 02, 2011 12:38 pm
by tangcla
Robbks wrote:Is this the same fault with the oil filters in the AVCS system that affected the WRX's of the same era?

I'm not sure, maybe. Basically in my case, it's showing 0 degrees at idle but when there are revs, it seems to pick up a signal and move. I'm trying to identify if I need a new hydraulic system, or whether it's just the sensor.

Re: Issues with hydraulic cam (left bank, intake)

PostPosted: Thu Jun 02, 2011 3:08 pm
by Gambit
Its a known issue where the filters to and from the AVCS Solenoids get blocked from debris, there is a service bulletin from Subaru out on it, its just a matter of cleaning and removing the filters from memory, there is more info on the issue somewhere but cant remember.

Re: Issues with hydraulic cam (left bank, intake)

PostPosted: Thu Jun 02, 2011 3:39 pm
by tangcla
If you can get it, that'd be very much obliged kind sir!

Re: Issues with hydraulic cam (left bank, intake)

PostPosted: Thu Jun 02, 2011 3:52 pm
by Robbks

Re: Issues with hydraulic cam (left bank, intake)

PostPosted: Thu Jun 02, 2011 3:59 pm
by tangcla
Great, thanks!

Re: Issues with hydraulic cam (left bank, intake)

PostPosted: Thu Jun 16, 2011 11:28 am
by tangcla
A slight update.

So they pulled out the filter, and it had actually disintegrated completely. So there's filter debris in the oil lines.
That's been cleaned out, and the scanner says the cams aren't moving (I think he said stuck on -50 degrees)

Put in someone else's AVCS and it moved, fine.
He's going to test my AVCS in the other vehicle to see if it moves - if not, then it's the hydraulic unit at fault. Cheapest and best-case scenario.

If not - block is coming out to see what else the problem is - and if that's the case, then I may as well get a closed-deck STi block :rolleyes:

Re: Issues with hydraulic cam (left bank, intake)

PostPosted: Thu Jun 16, 2011 12:27 pm
by Gambit
tangcla wrote:A slight update.

So they pulled out the filter, and it had actually disintegrated completely. So there's filter debris in the oil lines.
That's been cleaned out, and the scanner says the cams aren't moving (I think he said stuck on -50 degrees)

Put in someone else's AVCS and it moved, fine.
He's going to test my AVCS in the other vehicle to see if it moves - if not, then it's the hydraulic unit at fault. Cheapest and best-case scenario.

If not - block is coming out to see what else the problem is - and if that's the case, then I may as well get a closed-deck STi block :rolleyes:


whoo... hoo... closed deck 2lt block for the win.. hahaha

I hope its the best case scenario for you, goodluck with it.

Re: Issues with hydraulic cam (left bank, intake)

PostPosted: Thu Jun 16, 2011 1:15 pm
by Ben
That sucks Clarence :( Hope it gets fixed easily!!

Was it just 04-05 or are the 06 models affected too?

Re: Issues with hydraulic cam (left bank, intake)

PostPosted: Thu Jun 16, 2011 1:17 pm
by tangcla
Ben wrote:That sucks Clarence :( Hope it gets fixed easily!!

Was it just 04-05 or are the 06 models affected too?

Me too - and to think I should have sold my car off earlier this year, none of this would have happened!

I think mainly earlier models, but I don't know the specifics of it.

Re: Issues with hydraulic cam (left bank, intake)

PostPosted: Thu Jun 16, 2011 1:41 pm
by Robbks
the only rerason to pull the donk is if the cams need to come out completely.

the actuators should come off the cams without complete removal of teh engine though?

Re: Issues with hydraulic cam (left bank, intake)

PostPosted: Thu Jun 16, 2011 2:16 pm
by tangcla
Robbks wrote:the only rerason to pull the donk is if the cams need to come out completely.

the actuators should come off the cams without complete removal of teh engine though?

No- he's testing my AVCS unit in a WRX, if the unit works fine then it's not the AVCS. It'll be something else, and that's when the engine will come out. He suspects it's something in the head.

Re: Issues with hydraulic cam (left bank, intake)

PostPosted: Fri Jun 17, 2011 2:05 pm
by tangcla
Problem sorted - it was all the debris from the oil filter (metal mesh and plastic) that had deposited its way through the system and jammed the camshaft lobes, stopping the thing from rotating. He blasted out the oil channels under high pressure, and is confident almost all of it is out.

So $1500 later, I'm sorted - I guess I should be lucky, considering if I took it to a Subaru dealership, they'd have Buckley's chance of finding that problem and I would be at their mercy of having most of my upper engine replaced! :alcoholic:

Re: Issues with hydraulic cam (left bank, intake)

PostPosted: Fri Jun 17, 2011 3:23 pm
by Gambit
Thank goodness... and thank your lucky stars, it was not anything more serious.