subaru FB25 engine interchange

In reply to fess522 :

Hi fess522,

Going through swapping a 2016 Legacy into a 2013 Forester. Did you end up resolving the the codes? Also wanted to confirm if you ended up changing the crank sensor or not?

Just to follow up on my question to anyone looking for this thread for answers... I was actually able to swap the crankshaft sensor / bracket from the 2013 to 2016 motor. Also to anyone thinking of using the 2016 motor it went pretty smooth but there is a difference in how the TGV operates that is causing check engine light to come on. I believe they operate opposite of the 2013s. Working on a solution now but something to be aware if you do this swap

In reply to ejs22 :

im in the process of doing a 2016  legacy swap to a 2011 forester,  Glad i seen your post of  having issues. I noticed they the TGV's are all plastic and differnt. They are the Cast style on 2015 and back. I suppose i will just swap the whole intake setup to avoid  this issue. unless you were able to figure anything out?

https://www.subaruforester.org/threads/2011-tvg-wiring-error-code-2016-outback-motor-installed.799337/

i guess this is worth a try will see if swapping the wires will work? otherwise,  removing the chokes and keeping the gears is an option.

In reply to fhsoj :

I am really scratching my head on the TGV issue. Basically (the new plastic ones) run opposite to the old ones as you probably saw in that thread you posted. I tried switching the wires on pins 4 and 5 but I think the output voltage back to the computer might be too low for it to read it as "open". So the error message of "closed" keeps coming up.

When you clear all the codes and hook it up to the old TGV setup (before starting the car) do your codes go away?

Also getting the following codes in addition to the TGV codes (P2006 / P2007):

P0016, P0018 - Crankshaft Position Sensor and the Camshaft Position Sensor are out of alignment

I did use the 2013 crankshaft sensor and tone (?) wheel. This code doesn't pop up immediately, only after rev'ing the motor. I imagine if the tone wheel was off this would pop up a lot quicker. 

Cylinder 4 Misfire - I am 95% sure I have all the coil packs hooked up correctly so not sure whats going on here

Random Cylinder Misfire

If anyone has any suggestions, I am all ears! 

In reply to ejs22 :

I finally got my engine installed, 2011 forester MT,  engine was a 2016 legacy cvt with 60k miles.   I swapped the timing chain cover, and nearly all of the sensors.  I only became  aware of the TGV issue during this process of swapping everything. So i pulled the intake and addressed the situation as follows.  I removed the butterflys from the shafts, and also removed the Baffle wall  plate in the runner.  Using the old Sensor/motors on the new shafts, i had to  narrow the Tang that stops movment to allow for more range of motion as it's now the oppisite direction of new intake .  Now installed, the engine fired it up  and gave me  cam sensor and crank sensor codes immedietly, along with a p2004 for bank 1 intake runner stuck open.  After letting sit idle and clearing the codes,  The only  CEL that has stuck is a P2004, tried re clocking the sensor and still havnt solved it.  Engine runs good and no other issues so far.  i am going to try to keep messing with the Sensor to trick the computer, unlesss it's possibly the O2 giving a lean reading cause of the lack of butterflys on startup. but it seems it throws the p2004 before it even starts up. Will see if i can get any further  with this and post back..

In reply to fhsoj :

Congrats on getting it to work and thanks for the data point! If you're not in California, maybe you can just have a tuner delete P2004? 

For experimental purposes, I did the following:

Disconnected the newer TGVs 

Opened both with a battery (5V)

Started the car and I get an Open code (believe it was P2004)

This leads me to believe there is a second sensor (like you mentioned) reading a lean condition or maybe pressure. Curios if you have a scanner tool and are able to get TGV position voltage? When it is open is it reading 5V and 0V on start up? I just figured how to do this but it always reads 0Vs which is odd (even if I throw on the old TGV in the open position). Im using Car Scanner app with Subaru SSM2 selected. Wanted to see anyone else had success reading this value with an a scanner app or if the ECM is really reading OV.

In reply to fhsoj :

Quick question, did you swap to the 2013 crankshaft sensor?

In reply to ejs22 : yes i used the 2011 crank sensor, holder and tone wheel, as well as 2011 cam sensors.  IT will show a p2016 and 2018 in pending randomly, but never as a logged code. i cant see sensor voltages, im just using a cheap bafx bluetooth obd2 and torque app,  well still fighting the TGV codes. only getting a p2007 randomly. I have the old sensors/motors hooked up in the old alum intakes, but not installed. ( i actually just hacked off the motor/sensor housing with shaft and bearing from the throttle body) that's plugged in tucked off to the side.  i can clear the code drive for 20 miles  or miles and it stays off, or drive half a mile and  but randomly under a load in a tall gear it comes back, so still not sure if it's another sensor telling it nothing is changing.  might go the tuner route an have those parameters deleted.  engine runs good and smooth!   i paid 1000 bux for the 2011 forester 5mt with 130k miles. engine ran but was cooked an had terrible rod knock.  700 for engine and 150 for new clutch. I now have a good running forester 5 speed for under 2k.

update, after driving a few hunderd miles. The Tgv codes have subside, using the old sensors and housing frm the manifolds. i have had the crankshaft to p0016 and p0018 show up once or twice now and randomly a p0420 . but they seem to happen less  and less. maybe it's still learning. I  clear them and it stays clear for the next 20-40 miles or more.  The only thing i can come up with for the crank to cam sensor out of alighment, is maybe the triggers on the cam is different? When i swapped timing covers i noticed the Plate on the front of the cam phasesrs had differnt tone looking  tabs . I wasnt sure if those were the sensor triggers or the big slot in the side of the phaser its self?

In reply to fhsoj :

Thanks for the update. For me P0016 / P0018 show up pretty quickly, I didn't even think to look at the different tone tabs. That might not be an easily fixed issue if the tone tab sends  a different wave form to the computer than it is looking for...?

Im trying to picture your TGV set up:

• You have the old TGV / aluminum setup plugged in and set off to the side (i.e. not installed), so the computer is reading the old setup?
• You mentioned hacking something off from the throttle body?

Posting the different VVT sprocket for reference. Would a "valley" produce a different voltage on the magnetic sensor vs a "hill"?

2013 Subaru Forester:

2016

In reply to ejs22 :

I'm in a very similar boat to a lot of people here. I'm considering attempting to replace the engine assembly in my 2011 Forrester with a 2014 Legacy with matching 6th digit vins. All in even professionally installed it seems like bare minimum I'm going to save at least $1000. The one thing I wanted to know if anyone can help is that I've never done an engine swap before. I'm an appliance repairman by trade so I know my way around a tool set and I have a decent skill set when it comes to mechanical problems. However when it comes to cars I've only done the basics. I have changed spark plugs, brakes, and stabilizer links before on various vehicles. But I will say that when the engine first went out in my forester I looked under the hood and was a little intimidated. I had changed the oil plenty of times but all of that was right there in the front end staring me in the face. After reading this forum front to back a couple of times I feel like I can do this. I just wanted to hear from anyone with some knowledge on the subject to tell me if I'm just being overly confident or not. Is it a good idea to tackle this as my first engine? I'm just trying to weigh out all my options so I'm not stuck under a loan I'm finishing paying off with nothing to show for it at the end. After watching the videos of others removing this engine and looking at this thread it seems like it's just gonna take some wrench turning and patience. Am I wrong about that? 

In reply to BSing78 :

Work slowly and safely and refer to the instructions as often as you need to feel comfortable proceeding. You can definitely do it. 

In reply to Patrick :

From what I've gleaned from this thread; Would I be able to throw the flywheel from a manual transmission 2011 Forester on a 2013-14 Legacy engine, same sixth VIN digit, regardless of if it was previously attached to an automatic transmission? I can't afford a $1400 mistake... ¯\_(ツ)_/¯  Thanks in advance!

I swapped 2016 legacy engine into my 2012 Subaru forester.

Engine running strong. Sounds great. However the dashboard is Christmas Treeing (flashing lights).

I used a 2016 legacy intake. Because the swap wasn't possible with my Forester intake.

The wiring harness was crossed over. So I am super confused at this point

Hey All, I am actually in the middle of helping a buddy do this exact swap. He has a 2013 Forester and got a 2016 Forester engine because LKQ was $900 for that engine versus $3000 for a higher miles Forester engine. 

We got the engine pulled out the other night and I'm going back soon to help him get it back into the car. I think we're already on the right track, but it was nice to read through this and see that it's been done successfully quite a few times now. I just happened to stumble on this thread while browsing this morning. 

Gotta say, it's crazy just how tight that engine was to the transmission. Seemed like the dowel pins were a lot of it though, so they'll get cleaned up real well before it goes back in. 

Ok, so like I said in my previous post I helped a buddy do this swap and figured I’d summarize our thoughts in case it helps anyone else. 

As we know, this is putting a 2016 Forester Engine into a 2013 Forester because for some reason the Forester engines are like $3000 on LKQ currently for one with higher miles even, and he got the 2016 Forester engine for like $900. 

Engine Differences/Swapped Parts

• Valve covers. 
  • Swapped 2013 valve covers to the new engine so that the Forester coil packs fit properly.
• Timing Cover
  • Swapped 2013 timing cover  to the new engine so the accessories and belt could maintain the same routing. 
• Intake/Throttle body
  • We put the 2013 parts onto the new engine. 
• Engine harness
  • Entire 2013 engine harness was transferred to the new engine. 
• Flex Plate
  • Our new engine was from a CVT car, and the 2013 was a normal automatic car so we had to swap the flex plate over to the new engine. Double check to make sure if you need to swap or not. 
• Water Crossover Pipe
  • On top of the engine, under the intake. We put the forester pipe on the new engine because the one that was on it had an extra outlet. You could probably just cap the outlet, but we opted to swap over the old pipe. 
  • Since there is an extra outlet, naturally there is an extra inlet, or vice versa. Anyway, there was an open pipe on the bottom of the engine that also needed capped off. We believe the CVT transmission had cooling lines going to it, so that’s what these spots would have been for. More on that below. 
• Oil Sensor
  • The whole cause of the Forester engine’s demise was lack of oil, not helped by the lack of an oil sensor. The new engine has an oil sensor, which my friend plans to hook up to some sort of light in the cabin to prevent future catastrophe. 

Pain Points/Caution Points

• When fining your new engine, make sure to check what VVT setup your old engine is. I understand that some engines only have intake VVT, and some have intake and exhaust VVT. 
• The engine and trans were very difficult to separate from each other. Even once all the bolts were out and everything it took quite a bit of beating and prying to separate. I believe this is mostly due to the alignment pins sticking, so we made sure to clean them up very well before installing the new engine. 
• UNBOLT THE TORQUE CONVERTER BEFORE REMOVING THE ENGINE. Really this isn’t a huge deal, and was my mistake for not doing it first, but there is definitely the possibility to damage your torque converter or transmission if you aren’t careful. 
  • There is a nice rubber boot on the top of the bell housing to give access to remove the torque converter bolts. It’s easier to access if you remove the intake, but that kinda makes everything easier, so just go ahead and remove the intake first. 
• The timing cover doesn’t have an actual gasket, you’re just supposed to use RTV. We were not a fan of this, but it is was it is. Clean it up the best you can and get as proper of a bead of RTV on there as you can. 
• You will always forget a gasket. There were multiple trips to the parts stores and dealers for gaskets. Basically, any gasket you can easily replace while the engine is out, is worth doing. 

Swap notes from another page:

My buddy had found this post explaining the swap before this thread. Overall it explains it well, but it is easy to miss what I highlighted here. Since there's an extra cooling line coming off of the crossover pipe on top of the engine, it's going to have gone somewhere else, which needs capped off. 

Here you can see the open pipe that needs capped. Now, you could probably just put a cap on there, but we didn't want a chance of an ait pocked, so we decided to take the time to take that pipe off and plug the hole closer to the block. (Which would've been MUCH easier if we realized to do that before the engine was in the car...)

Transmission notes:

Thanks to Woody's thread about Subaru torque converters, we were ok, but if your torque converter pulls out from the transmission at all, make sure it gets seated back in PROPERLY. 

Access for torque converter bolts:

Hope this helps!!

Hi everyone,

I had to scrap the engine I was working on before and start the engine swap from scratch. I have a 2011 forester with a "C" as the 6th VIN digit. I bought a 2013 Legacy engine with what I thought was the correct VIN matchup (6th digit "B", California Emissions). 

I did the swap and the engine runs fine, but I'm getting some codes. 

P2004 - Intake Manifold Runner Control Stuck Open - Bank 1

P050A - Cold Start Idle Air Control

P0018 - Camshaft Position Correlation Bank 2 Sensor A

Anybody have any ideas? Have I messed up and put in an engine with the wrong emissions profile? I'm about ready to throw my tools in the river so any help or guidance would be very appreciated

Edit: Should have mentioned: I replaced the TGV valve motors and that changed nothing

Greetings,

Thanks for the great guidance on this thread.  I just swapped a 2015 Legacy FB25 into my mother in law's 2012 Forester.   I guess I got lucky, because it started on the first try.  I've only driven it about 5 miles, but no codes yet.  Here are a few things that worked for me:

1. Move all sensors from the old engine to the new one along with the wire harness.

2. Move the timing chain cover from the old engine to the new one.  I had to do this to keep the original accessories and belt.

3. Loosen the upper transmission mount (attaches to the firewall) during reassembly.  This made it so much easier to get the engine and transmission aligned.

4. Support the exhaust manifold with a jack and use a pry bar to pop the flange over the studs.  The manifold seemed to have curled up a bit while it was off the original engine.  The flange holes were misaligned with the studs by ~1/8".

What did you do for the TGV/Intake manifold?

Buddy and I picked up a cheap 2011 forester that needed a motor, so I bought a 2016 Legacy FB25.   I guess I missed all the intake manifold/TGV chat when I was researching the later-year FB25 swap, and now I'm not sure I want to bother with it if it's going to throw codes.

Maybe someone who knows more can clarify the year splits and changes to the metal lower intake TGV vs all-plastic.

Love the info in this thread so thank you everyone for posting!

Well I ran across a thread elsewhere about how to fix the TGV issue by moving sensor magnets, have not tried it.

https://www.subaruforester.org/threads/2014-how-to-install-a-2017-engine-into-a-2011-2016-vehicle.836125/

Also a document discussing the technical changes involved with the TGV

https://static.nhtsa.gov/odi/tsbs/2014/MC-10069730-0699.pdf

I am looking into differences in Denso part numbers used on the TGV between 2011 and 2020

Denso 012010-6110(bluegreen 2011-2015), 012010-6111(green 2016-2019) & 012010-1091(blue 2020-) approx years

This might be informative too

https://subaru.oemdtc.com/2984/intake-manifold-tumble-generator-valve-tgv-design-change-2017-2020-subaru

In reply to Skenton :

Do you know if the 2015 legacy engine has the same intake differences as the 2016?  The '15 engines are more available than 2013/14 but I'd prefer to stay away from the intake issues and cam/crank sensor issues if possible.