AVCS Checks and Diagnostics

[Travis19STI]

I have a 2019 STI with some AVCS issues that are sticking specifically p0019

Had the water pump seize on me and threw had to change the timing belt.
Changed belt, tensioner and pulleys, water pump, both bank 2 AVCS solenoids, both bank 2 cam gears, and have confirmed timing 3 times as first belt was stretched and now after all that still have the code sticking,

My main reason for asking here is two reasons, when my motor was built at IAG the banjo bolt was replaced by an AN fitting setup for the intake AVCS solenoid, apparently threads were ripped out and they tapped to 1/4 NPT and then made the line from there. Could this be the cause? Or could it be that i messed up and got two of the same AVCS solenoids for the exhaust and intake when they should be different?

[bigBADbenny]

Do you have AP or Open Source obdii interface for datalogging?

That’s the shortcut to a successful diagnosis…

Just googling the code says it’s bank 2 sensor B, so that’s the LHS LHD drivers side *exhaust* (lower side of the head) AVCS solenoid etc.

So the exhaust oil control valves (OCV’s) are supplied with engine oil directly from the heads, via a mounting block aka manifold that houses both the OCV and the mesh oil filter. The exhaust OCV manifolds are supplied as a complete unit including the filter and you may also need the required gasket.

You might get away with just cleaning the filter if, for example, doing the side to side OCV swap doesn’t result in the opposite bank code being thrown, as per the advice in the OP of this FAQ.
If doing the OCV swap, and the opposite bank code is thrown, then it’s likely the affected OCV is the culprit.

[bigBADbenny]

Notes on installing reinstalling avcs sprockets:

The main thing is to not damage the camshaft during install or reinstallation: the alignment pins can be made to jump out of their holes causing major damage. So it’s important to not use impact guns on the sprocket to camshaft bolts. For uninstall it’s a good idea to use a holesaw to cut the flange from the bolt head, allowing the bolt to be freely spun out. Reinstall: seat the pin in the hole properly then hand tighten, then torque against the sprocket holding spanner or locked belt.

[bigBADbenny]

ALVS leaks

If the thread is damaged where the diagnostic oil pressure sensor is located, there is a thread repair kit available.

The “correct” tightening procedure for the oil pressure sensor is finger tight then a quarter turn, using a liquid thread sealant eg Permatex 80632.

The related ALVS control components can also leak at the “VVT“ control solenoid and at its housing gasket where it meets the head.

If you have a mad rattling noise in either head, it can point to a fault with the ALVS profile switching mechanism, like a clip or bracket that slips out of position. Pulling the cam covers will allow inspection to confirm the issue. If you’ve experienced this issue please send me some info on the problem and it’s resolution

Diagrams are available in the online parts catalogue, eg USDM 2012 Legacy Outback 2.5i:
https://parts.subarumorgantown.com/a/Su ... 06-01.html

ALVS oil pressure switch repair kit: https://www.google.com.au/searchq=subar ... repair+kit

If your ALVS issue has related engine diagnostic trouble codes (DTC’s) aka flashing lights on the dash be sure to get the diagnostic codes and lookup the procedures in the factory service manual: viewtopic.php?f=6&t=34980