P0016 on a 60k mile car

[SLVRSRFR]

Originally Posted by precurse

I'm likely going to pressure my local dealer to eat some of the cost of the useless cam sprocket swap. They're claiming the sprocket can cause a "permanent" lockup in the ECU which needs it to be replaced. I'm calling BS on this, since I've read on here that others simply replacing the ECU and the problem goes away.

I was told the same thing by my dealer, and I trusted his opinion because it was coming straight from the Fixed Operations Manager, who is on a first-name basis with me and is a total no-bullshit kind of guy.

Apparently the learning values in the ECU get thrown out of whack when there's a fault in the sprocket, and there's no way to reset them, necessitating the ECU swap. I have no way of knowing if he is wrong or not, but he really had nothing to gain by lying to me, so I gave him the full benefit of the doubt.

Glad to hear that Subaru Canada is extending goodwill to you like they did to me.

Hope it all works out in the end!

[Ultramaroon]

Originally Posted by SLVRSRFR

Apparently the learning values in the ECU get thrown out of whack and there's no way to reset them, necessitating the ECU swap.

Hmmmm... This is very interesting! Seems plausible.

~~~edit 20180120~~~
I've updated a couple of my posts to keep this in mind.

[ApexEight]

I'm really hoping just an ECU swap will fix my problem. I got one of out a 2015 that should be delivered today.

I didn't want to spring for the sprocket change as it's a very involved job and the car is my daily. Also, it drives perfectly fine, just like it did before the P0016 showed up, though limp mode sucks.

And every time I read the code off of Torque, it shows the P0016 as a Historical Code, so this, based on what I've read and what @SLVRSRFR said, I think it's really just an ECU learning problem.

I'll report back.

[precurse]

Originally Posted by SLVRSRFR

Apparently the learning values in the ECU get thrown out of whack when there's a fault in the sprocket, and there's no way to reset them, necessitating the ECU swap.

That's good to know. Thanks for sharing!

Playing the devil's advocate... Coming from a computer science background, I still feel that this is an ECU design flaw. Excluding the circuitry, everything on the ECU is more or less just executable software code and flash memory for storing data. Unless there's physical damage done to the circuitry causing this (which it doesn't seem like it is), then replacing a $1200 part just to clear some bad memory values seems like poor engineering to me.

Also, if the sprocket causes a bad code in the ECU, I would think that the TSB would state to replace the ECU along with the sprocket.

Just my 2 cents

[ApexEight]

Changed out the ECU today. CEL has not returned.

[precurse]

Originally Posted by ApexEight

Changed out the ECU today. CEL has not returned.

That's good news! Another example that I've read on here where changing the ECU fixed the CEL.

Curious.. Is your odometer ok after the change?

[ApexEight]

Originally Posted by precurse

That's good news! Another example that I've read on here where changing the ECU fixed the CEL.

Curious.. Is your odometer ok after the change?

Odo is fine but my average MPG was reset, as was the option to show what gear I'm in. I had disconnected my battery.

And yeah, if I had some serious drivability changes, like a bad idle, I would've suspected I also needed a sprocket change, but I guess I'm somewhat lucky.

[ermax]

Originally Posted by precurse

That's good to know. Thanks for sharing!

Playing the devil's advocate... Coming from a computer science background, I still feel that this is an ECU design flaw. Excluding the circuitry, everything on the ECU is more or less just executable software code and flash memory for storing data. Unless there's physical damage done to the circuitry causing this (which it doesn't seem like it is), then replacing a $1200 part just to clear some bad memory values seems like poor engineering to me.

Also, if the sprocket causes a bad code in the ECU, I would think that the TSB would state to replace the ECU along with the sprocket.

Just my 2 cents

My thoughts exactly! Everytime I hear about ECU swaps fixing stuff it leaves me scratching my head. Typically when a computer (hardware) is failing you have all kinds of stuff going wrong and totally random. It isn't like a PC with a UI where users do stuff to mess things up. With all the stuff you can do in TechStream you would think there would be a reset for the cam gears. You almost wonder if the real fix is simply the tampering with the wiring harnesses during the ECU swap.

[precurse]

Originally Posted by ApexEight

Odo is fine but my average MPG was reset, as was the option to show what gear I'm in. I had disconnected my battery.

And yeah, if I had some serious drivability changes, like a bad idle, I would've suspected I also needed a sprocket change, but I guess I'm somewhat lucky.

I noticed that the gear indicator in mine disappeared when I had ECU issues (or replaced the battery). Unfortunately I bought the car with it turned on so I have no idea how the previous owner turned it on.

Were you able to get it back?

[Tcoat]

Originally Posted by precurse

I noticed that the gear indicator in mine disappeared when I had ECU issues (or replaced the battery). Unfortunately I bought the car with it turned on so I have no idea how the previous owner turned it on.

Were you able to get it back?

It's default setting is off so when you disconnect the battery it goes back to off. The instructions on how to turn it back on are in the owner manual. It isn't difficult.

[ApexEight]

^

No problem getting gear indicator back on. Day 2 of no CEL with just an ECU swap. Feels like I gained 40 WHP now that I'm out of limp mode lol

[Ultramaroon]

Well, spank my ass & call me Judy!

[precurse]

Now I'm kind of regretting paying Subaru over $1200 to fix this when an $80 ECU swap might have resolved it to begin with.

Ah well...

[rusty959]

So an update on my situation, Subaru wanted $1600 to do more "Diagnostics" and then Subaru "might" pick up the tab, so I said no and am working on the cam sprocket myself. I've now got them out, at which point I realized I don't really know what I'm looking for. I at one point saw an image posted by I think @Element Tuning that showed the flappy spring door being messed up on the back, but can't seem to find it now.

[edit]found the post, was actually @AVOturboworld at http://www.ft86club.com/forums/showthread.php?p=2649000, and it looks similar, but not sure if it applies since it was sitting flush when I pulled it out

Anybody out there know what to look for? I can't find my snap ring pliers so can't take it any more apart tonight.


Exhaust Back:

Intake Back: Spring was in place when I pulled it out.

Then I gently touched it and it popped out like this, which reminds me of the image I saw once:


I'm probably going to replace them regardless while I'm in here, and I'll likely pull the other bank off as well just to compare, but it would be nice to know if they are or aren't broken, and if I wasn't supposed to touch that spring plate to not do it to the other side, lol.