AVCS VVT angle out of sync diagnosis MY07 GT B

[bigBADbenny]

The only issue I had with the air pump & tube was/is that it's in the way of removing the 17mm bolt that sits atop the banjo bolt for the LH avcs solenoid oil line...
But the issue may well be with the LH avcs cam gear itself...
Ill go through the factory advisory diagnosis procedure again.

[bigBADbenny]

Posting relevant research pages:
http://legacygt.com/forums/showthread.p ... 31462.html
http://legacygt.com/forums/showthread.p ... 18887.html

[XT_for_me]

Sorry Bruce but we NEVER disable the P0244 CEL code. It's an extremely important safe guard. As for the secondary air pump, its a common failure in the earlier cars that used it and may become more common in later cars as they age. The official Subaru repair is typically around the $3000 mark just to fix an item that works for 30 seconds after a cold start and it purely for emissions control in that time. If you consider the emissions that a 12 month old car makes compared to a brand new car just in normal driving due entirely to normal wear and tear then not having the secondary air pump working for 30 seconds fades into insignificance.

Getting back on topic, the AVCS system adds a lot to the performance of the car in both power delivery and economy (emissions also) so having it working correctly is important.

Ok let me get this straight.... Udisable the secondary air system with out knowing if the vavles are in the right position...!!! Ie full open... To me sounds doggy

You seem to have it crooked rather than straight.

[<GB>]

Didn't answer my question!

[bigBADbenny]

I have this symptom, I thought it was unrelated but now the penny has dropped:
Trying to hold 1500rpm, revs hold then drop to around 1300 AND the car (engine) begins shaking from side to side.
I logged that: LH stays steady, RH oscillates! That was on the stock tune as well.
Ominous chattery sound has developed emanating from the LH side: nek minit!
Pic of graph soon.

[<GB>]

So it's misfiring? Or vacuum leak?

[bigBADbenny]

Stuffed avcs inlet cam gear??? OCV solenoids?? Oil lines clogged?

[<GB>]

Fast edit there lol that's good might be worth replacing it

[bigBADbenny]

Check this out


Its been going on for maybe... a month?
I noticed originally when the vac hose was off and I couldn't work out why it wasn't returning to idle, hovering around 1200rpm instead.
After a week or two I noticed the vac/boost line had popped off, put it back on all good.
No observable issues in normal driving, just this @ around 1500rpm.

I had thought the slightly shakiness just off idle was simply old, stuffed engine mounts...
But this is symptomatic of something else entirely...

Once again, the graph represents me trying to hold 1500rpm in neutral.
Start: The revs hold then suddenly drop to around 1200-1300rpm and the engine shakes from side to side.
Giving it more acc gets it steady again then back to Start.

I'm hoping for even more opportunities to improve my Lib whilst fixing this ahhh minor issue lol

[bosc0]

Benny! My car was throwing code 0021, i looked into what he issue may be and it seems it's quite common of the solinoids to fail or become clogged (as you know).

It's piss easy to remove them and inspect/clean. In my case the car was getting serviced anyway so i asked they be checked and cleaned. Turns out the mesh had been remove previously and they just needed a clean.

I also found that to replace the units was heaps cheaper from the US, $85US each IIRC.

Pull them out and take a look Benny. Will take 3 minutes.

[bigBADbenny]

I most certainly will!
I was in the area yesterday hopefully fixing another issue: I'd noticed that the oil on the LH rocker covers was pooling a little around the oil filler base. I mentioned it to Ashley etc. at M&L when I was grabbing the filters & crush rings - they suggested a replacement O ring for the filler neck base. $10 & 30min work later... Used degreaser to blast the LHS clean & rinse with the hose... Too early to tell if that's fixed what had been diagnosed as leaking rocker cover gaskets, but looking good so far. The old O ring was flat, hard, cracked all the way around & broke easily when bent.

Borked oil filler O ring^^^

Hoping this is what saving $400-800 looks like ^^^

Reinstalled, degreased and rinsed off^^^


The point being: my mechanical confidence is very much approaching the level required to DIY the solenoid fix
Probably typical n00b fear/paranoia and getting over that in a hurry - bear with me...
RTM on LHS air pump tube removal ATM

At this point I'm looking to clean the solenoids, UEC, mineral + filter flush, refill with Syn + filter...

[bigBADbenny]

Did UEC this evening as a precursor to an oil change.
Thicker oil is being recommended by a trusted source, as a means of increasing oil pressure in the lower rev range.
Post UEC logs:



Its still a bit allover the place^^^

I'm lucky to have some other members with the same issue, we're going to pool resources get this fixed, so send a PM if your rig is shivering at around 1400rpm in neutral...

Earlier model Subarus had oil filters in the oil control lines which would block, and ultimately starve the turbo of oil.
Its looking like postFL's dont have that particular issue. Indeed my issue is not even causing a CEL (ATM...)

So I'm feeling less paranoid/more edumacated

[KiDo_Tuning]

Use Learning View to do a full Ecu Reset as well. The Oil Control Valves Self Learning Parameters might need resetting

[bigBADbenny]

I shall do!
The above is back on tune revD.
I have to go through my LVs to see whether reflashing = resetting with the MY07 ECU.

I had the stock tune loaded for around a day for testing, intriguingly the IAM didn't get over 0.5.

My guess from the logs is that the ECU is aware of the VVT advance angles vs OCV duty and compensates to catch up thus the oscillations at 1400rpm?

[KiDo_Tuning]

I shall do!
The above is back on tune revD.
I have to go through my LVs to see whether reflashing = resetting with the MY07 ECU.

I had the stock tune loaded for around a day for testing, intriguingly the IAM didn't get over 0.5.

My guess from the logs is that the ECU is aware of the VVT advance angles vs OCV duty and compensates to catch up thus the oscillations at 1400rpm?

There is a table for OCV duty that is undefined. It sets duty percentages similar to how WGDC works, with minimum and maximum OCV limits to reach target.

Usually it is dirty filter baskets but oil does influence the solenoids(as seen in Veloci thread)

Reflashing resets FLKC and AF#1 Learning but does not clear DBW or OCV or a few other tables.

How did it feel going back to the stock tune?