subaru FB25 engine interchange

In reply to SubArooDude :

Fuses maybe?

Did I say sanity?! Hahaha, that's gone out the window! I've been driving the thing, even while it's had this check engine light. It developed a bit of a knock for some reason. I hooked up the old tumblers with the original magnets, switched the wires back and you know what? One stays closed, the other one stays open. Explains the poor running condition. Check engine light still on of course. Tried clearing it, disconnect battery for 30+ min, switch magnets from side to side, switch tumblers from side to side. Nothing. I'm starting to wonder if somehow I switched the magnetism in the magnet, or, more likely, my ECU is broken. Also, I'm pretty sure I've spent more time troubleshooting this than thee entire engine swap combined. Still not giving up though. I'm going to sacrifice a connector from the old harness and do some testing yet.

Skenton said:

In reply to SubArooDude :

Fuses maybe?

No, sadly. I checked voltages at both plugs.

Ignition on(not running):

PIN 1: +12V

PIN 2: Ground

PIN 3: +7.3V

PIN 4: Ground? Produces 12V with positive probe in PIN 1

PIN 5: with POS probe in PIN 1, this pin produces a fluctuating voltage 10-11V

Keep in mind this is without the sensor/actuator plugged in, just testing the plug. I'll report back on more findings.

In reply to SubArooDude :

I read this somewhere, and do not know if the information is correct, but apparently if there is a problem with only one TGV valve assembly, it will throw codes for both. Maybe that will be helpful?

Along those lines, does unplugging the TGVs one side at a time and clearing codes change what new codes pop up when test driving afterwards? Then again with both sides unhooked what codes do you get?

Likewise, does (briefly - the FSM says 10 seconds max to avoid overheating) feeding 12v to actuator motor pins 4/5 in both orientations while removed from the manifold make the motor spin both ways? As I recall, someone up thread mentioned that they had a bad TGV motor/sensor on their vehicle before they started the swap. Those codes might be telling the truth   Swapping the actuators side to side and seeing if the codes change might be informative too.

2011 Forester with 2016 Forester engine swap.  My Son and I did the swap over Christmas vacation. I used the 2016 intake so I had those codes, and I forgot to swap out the 2016 Timing plates. The car had a bad TPS code about 2 weeks after we got it. So those codes have been up since December. Runs great, 26mpg consistently even with the codes, which is what his old car got, no complaints there. We planned to work on it this summer.

This week he spotted an leak, I knew what it was as soon as he said it. The old engine got hot, I should have replaced this but thought the rubber bushing would keep it sealed. I chose poorly, The donor engine had one, so I dunno what I was thinking.  

Since we had to take half the stuff apart to reach that, we are now working on the rest while its nice outside. 

I wanted to share a picture of the Plug for the Passenger side tube.  Big bolt, it cant have threads to the head of the bolt. It has to have the smooth part at the head of the bolt so the coolant doesn't chase the threads. My Son drove all over the state for College tours. Runs like a dream. Bad dream the check engine light is on. lol jk.

This is on the back side of the engine passenger side. 

(Son drove my car after he got TBoned, totaling his old car.  While in my car, the heater core hose sprung a small pinhole leak, got hot check engine light on and he pulled over called me. I got there finding the pinhole, added water, turned on the heater and drove home. When his new to him Subaru blew a radiator hose (4in tear)... He followed my lead. Added water, turned on the heater and drove it home. No temp gauge and young no experience... <BOOM. lol  I was out of town so he didn't just call as the normal reaction would have been. He has done most of the work, excellent learning experience. I'm pretty sure it is what changed his choice on college majors. (accounting to engineering) ) Thank you for all your brain power in this adventure. Truly. 

Great picture of the hose plug. Thanks!

Quick update, it's fixed now! (At least I'm pretty sure it is)

Long update, involves confusion. I had originally followed the steps precisely, when it didn't work, I backtracked. Swapped my wires back, put the magnets and actuators back on the original tumblers connected next to the engine and still had codes(as previously mentioned). So much confusion. I made sure the wires were in their factory positions for Pin 4&5 on both sides, matching their colours as per the diagram I previously shared. However, both actuators were moving the same direction leaving the passenger side(bank 1) open, driver side closed, scratched my head on this for a while, double checked my wires, swapped magnets, did many things. Then, I decided to swap the wires on the passenger side for P4&5, opposite of the factory wiring, and, to my surprise, they both moved correctly, and the code disappeared. (makes sense why flipping the wires worked, but not why it worked in the non-factory position) Some sanity returned, there was hope now, that it might work.

I proceeded to follow all the instructions again, and, when I got in the car and turned it on, cleared the code, and then got a CEL. Disappointment. This time only P2004, no P2005 though. So I retimed the magnets, several times, still P2004(bank 1 stuck open). So, I timed the magnet that it would be over the sensor when it was closed, not opened (passenger side only). And it worked. Still confused though...

Now I have the passenger side pin 4&5 wires technically in the factory positions, and the magnet over the sensor in the closed position, and it works, no CEL. I don't understand why, I haven't quite wrapped my brain around it. Driver's side wires are swapped and magnet timed for being over the sensor in the open position.

Does anyone have pictures of their pin 4&5 wires from both sides, after the engine swap, in the working setup? Curious if it's different than mine.

In reply to SubArooDude :

Great to hear you think you got it! So you have one magnet over the sensor when the butterfly is fully open, and one over the sensor when it is closed? Well if it works, it works! :-). I'll try and grab a picture of my wires tomorrow and upload. 

Keep in mind that the left and right TGV butterfly valves rotate clockwise on one side and counter clockwise on the other side. Speaking from experience, it is easy to confuse open and closed from the outside.

Somewhere upthread is a diagram from the FSM showing wire colors for 2011, what year is your donor engine and I will see what I can find for that year, they may vary.

<Edit - Nevermind about the year, we are reusing the old wiring harness/>

Are you using the short black magnets from the old engine/manifold? They are marked A and B and are mirror image as to the placement of the North and South magnetic poles. This allows the old ECU to "see" the same signal on both sides when open or closed because the same N/S pole is over the sensor. Given the their curved shape this is the clockwise end of one magnet and the counter clockwise end of the other magnet. The long white magnets from the new donor engine are both identical which requires the new ECU to look for different signals for open or closed on either side. I tinkered with them a bit to see if they could be clocked usefully but since we are using the old wiring harness and ECU I did not spend much time on it.

Here are pics of my 2011 wiring harness with pins 4 and 5 swapped.

Drivers (left) side:

Passenger (right) side. Unplugged so I could get a decent picture:

Maybe someone is interested in my FB25 exchange from a 2011 Subaru Forester to a 2016 Legacy engine.

Certain things have to be done as described in many forums on the internet. Sensors, cam and crank
reluctor wheels and sensors have to be changed to 2011 versions.  

In my case I decided to use all the 2011 peripherals, except the front timing chain cover with the oil
pump to accommodate the missing idler wheel mount.  I made a bracket that mounts under the alternator
that holds the idler wheel.  The best part is that these are all easy mechanical fixes.
To avoid playing around with the dreaded TGV sensors, I decided to make myself adaptor plates that
bolt on the maifold and the engine.  The plates morph one intake shape to the new longer intake ports
on the cylinder heads. It will use the original seal hardware.  The only thing you need is longer bolts
and to extend the EGR pipe. The plates are 15mm thick.

If anyone is interested in an easy way to overcome the TGV problem, I can definitely make additional
adaptor plates and sell them for a fee and make them fairly quickly. Feel free to contact me.

See attached pix.
 

In reply to VANPA :

Wow, great work on the adapter plates! Before I started my swap I posted in a forester forum that I really wished a fabricator made an adapter plate to do exactly that. It would have been an easy sell to me if those were available then. Include the pulley bracket and then you have your own bolt on engine swap kit! 

In reply to Sodapopdave :

Thanks Sodapopdave. For me it was a choice between messing with electronics and don't know how reliable that would be in the long run. And a bonus of the longer intake is that it sounds better and  so far better gas mileage. Didn't think 15mm would make a difference 

Didn't think 15mm would make a difference 

that's what she said

In reply to jdf60 :

Would all the 2011 forester parts bolt onto the 2015 outback block itself and work without issues?

That pretty much describes the process.  It assumes you use the 2011 computers, wiring harness and sensors as well as the mechanical parts discussed here. The TGV fix requires some additional simple modifications if you use the new manifold. With the adapter plates and the old manifold the TGV flow will be down the "wrong" side inside the new block which *MIGHT* effect emissions a bit for the few seconds it is active at cold start. Subaru changed the TGV direction for a reason discussed in one of their TSB documents. Dunno if there was any change to the inside of the castings at the same time.

In reply to VANPA :

How much for a set of these and how long would it take to make and ship?

In reply to dstubson :

Hello, feel free to  email me. 

joe.cncguru@gmail.com 

for the price and I need the zip code for shipping cost

Cheers

In reply to VANPA :

Emailed. Thanks

In reply to Patrick :

Hi Patrick. I followed the thread between you and Dustin about engine swapping the 2011 Forester for the 2014 Legacy. My partner's engine no longer works because of the oil burning problem, the oil light also never came on until it was already too late. I see that you're from Cleveland. We also live around there (Akron). I literally created an account so I could try to contact you, but I can't send private messages yet until an admin approves me.

Her car is currently with her mechanics in Perry, OH. And I've sent this thread to her mom, who will hopefully send it to her mechanics to read over. I think it would save them a huge headache and would also save my partner a lot of money. I know this is a long shot, as this thread is several years old, but I was wondering if there's any chance you could DM me your contact information so that I could forward it to her mechanics in the hopes that if they do go this route of engine swapping you could maybe provide some help or something. I don't know anything about car parts, but I am an avid researcher and was lucky to find this thread.

Here's hoping I hear back from you!

_David

In reply to VANPA :

 Hi there im in need of some of these plates! I would like to purchase several sets from you. I have sent a few emails, but they may have been blocked, by spam blocker.

I'm was going to PM you by phone number, but im too new for PM

Im swapping a 2014 Subaru forester for a 2015 legacy engine. Subaru number 47 for me in the past 6 years! 

I want to take a moment and think everyone in this thread as it some amazing information! I was very excited to find all this!

-Cheers  

Dee

I am sending this from Australia.  I have an 11/2011 build Forester FB25 engine with manual transmission.  It is an oiloholic using about 4qts of oil every 1000 miles. The car has only covered 84,000 miles. Subaru Australia state this is normal.  Rather than swapping engines, I was thinking of just buying a set of standard size piston and rings and honing the bore.  I would replace the big end bearings but probably not split the block and leave the main bearings as is.  Has anyone thought of this as an option rather than taking a chance with a used engine and the problems that might go with it?  I would expect the cost of parts to be cheaper or on par with a cheap second-hand engine.

The factory warranty repair was to swap the short block, but I believe the real issue was QC issues with the original piston rings so it sounds reasonable to me to do a rebuild if you can get the parts. I was considering it until I dropped the oil pan on my 2011 and discovered a piston rod hanging out of one cylinder which was beat to death by the crank after the rod cap broke. I could not find much in the way of parts at the time I was looking. Places here state side were blaming "supply chain problems". So, I got a used engine.

Maybe you will have better luck. You might just try a "re-ring" kit if such is available.

Skenton said:

Keep in mind that the left and right TGV butterfly valves rotate clockwise on one side and counter clockwise on the other side. Speaking from experience, it is easy to confuse open and closed from the outside.

Somewhere upthread is a diagram from the FSM showing wire colors for 2011, what year is your donor engine and I will see what I can find for that year, they may vary.

<Edit - Nevermind about the year, we are reusing the old wiring harness/>

Are you using the short black magnets from the old engine/manifold? They are marked A and B and are mirror image as to the placement of the North and South magnetic poles. This allows the old ECU to "see" the same signal on both sides when open or closed because the same N/S pole is over the sensor. Given the their curved shape this is the clockwise end of one magnet and the counter clockwise end of the other magnet. The long white magnets from the new donor engine are both identical which requires the new ECU to look for different signals for open or closed on either side. I tinkered with them a bit to see if they could be clocked usefully but since we are using the old wiring harness and ECU I did not spend much time on it.

So is the ECU looking for a certain polarity when closed and when it's open? For example looking for a North on both sides when open and South when closed? Or is it just looking to sense a magnetic field, and no magnetic field?