2015 BRZ wont turn over after clutch and flywheel install

[khrono]

I had a bad throwout bearing at 80k miles so I installed a brand new one along with the clutch and flywheel. After putting back everything the car wont turn over. Car cranks like normal but it just keeps cranking until I let off the clutch. I put my oft tablet in and it says I have a P0335 error or crankshaft positioning sensor error. I don’t recall touching anything near the front of the engine. The ony thing I can think of is the metal plate behind the flywheel. I am not sure what it is called.l, but it has angled teeth caving in one side. It dropped when I took off the flywheel and I put it back with the teeth facing the transmission. Did I install it backwards and the teeth should face the engine? Is this what is causing the Code and car not starting? I hope anyone can chime in with their experience since I have been obsessig over this install for days. Thank you.

[sfruski]

First guess is that you knocked the connector off the crank position sensor. It is located top-center at the back of the engine.

It could be the plate, as that is what the crank position sensor reads from, but I don't remember which way it goes off hand.

[Dr. BRZ]

Most likely you put on the plate backwards

[khrono]

Originally Posted by sfruski

First guess is that you knocked the connector off the crank position sensor. It is located top-center at the back of the engine.

It could be the plate, as that is what the crank position sensor reads from, but I don't remember which way it goes off hand.

Ok thanks for the advice. I will check to see if I can locate the sensor and report back.

[Ultramaroon]

Originally Posted by Dr. BRZ

Most likely you put on the plate backwards

+1

[khrono]

I didn’t see any connector that looks like the sensor from the google images. At least nothing near where I was working. Any pics for our cars on the location? As the inline searches only show stis and wrxs.

As for the plate thingy — anybody know the name of it? Is there a way to check that it is the problem for sure as I would want to fix anything else if I have to jack up the car again.

Side note the first time I put the transmission bell housing back on to the engine block it knly goes through the thread maybe 30% with the tips exposed. Is it right to screw on the rest and tighten the of the bolts to secure the transmission? I have tried all the ways online of alugning the tranny and engine and jacking the headers/oil pan to make it easier, but no matter what J did the besg I got was 30% through. Is it suppised to slide in 100% easily if I do it right? Sorry for the double question. Its just that the guides and videos make it seem far easier or I am just not as mechanically inclined.

[projek_01]

Oh dude, that tranny isn't aligned if you cant bolt it back together 100 percent easily. Did you use the clutch disk alignment tool and pressure plate torque sequence?

You sir are very brave for tackling this yourself without the help of someone mechanically inclined if you are not yourself.

Although your crank sensor should still work if your tranny is not bolted up. Something is probably not plugged in or installed backwards. I would take it apart again and redo it with the help of a service manual and a mechanically inclined friend. The last thing you want is to
1. Drop some bolts at 7k rpm
2. Crack your brand new clutch disk or damage the input shaft splines by forcing it in

[Ultramaroon]

Yes, the teeth on the plate face the engine so the proximity sensor can detect them. I don't know what subaru calls it but the general term for that part of an encoder is called the scale. The scale and prox sensor together are called a rotary encoder.

[khrono]

Originally Posted by projek_01

Oh dude, that tranny isn't aligned if you cant bolt it back together 100 percent easily. Did you use the clutch disk alignment tool and pressure plate torque sequence?

You sir are very brave for tackling this yourself without the help of someone mechanically inclined if you are not yourself.

Although your crank sensor should still work if your tranny is not bolted up. Something is probably not plugged in or installed backwards. I would take it apart again and redo it with the help of a service manual and a mechanically inclined friend. The last thing you want is to
1. Drop some bolts at 7k rpm
2. Crack your brand new clutch disk or damage the input shaft splines by forcing it in

Hmmm I didnt use any specific torque sequence for the pressure plate. Inly the flywheel. I used the alignment tool fully seated and I thought it would be aligned enough. If I did f up the transmission would I be able to see the damage when I take it back apart? Loose pilot bearing or spline damage?

I will look up the pressure plate torque sequence when I redo it.

Thanks for all the suggestions!

[khrono]

Originally Posted by Ultramaroon

Yes, the teeth on the plate face the engine so the proximity sensor can detect them. I don't know what subaru calls it but the general term for that part of an encoder is called the scale. The scale and prox sensor together are called a rotary encoder.

Ah thank you for explaining that. I definitely flipped it then because originally I thought the clearance was too little facing the engine, but I guess that is how it is meant to be.

I will report back when I redo everything more carefully this time.

[celek]

Originally Posted by khrono

Ah thank you for explaining that. I definitely flipped it then because originally I thought the clearance was too little facing the engine, but I guess that is how it is meant to be.

I will report back when I redo everything more carefully this time.

If it is bent you will get sync loss and issues as well. option is to by a new plate from Subaru and just put that in. or save the $30 or what ever put it together hope it is not bent so you don't have to take it apart again a 3rd time.

[Irace86.2.0]

Check out my build for pics of the plate and proper orientation.

[khrono]

Originally Posted by Irace86.2.0

Check out my build for pics of the plate and proper orientation.

Nice Build! Thanks for the pics too.

[khrono]

I just wanted to update my post. I went back in slowly over the past few days and took apart the car a second time. I will say that it was much easier this time around as I knew what I was doing already.

The rotary encoder plate thingy looked fine so I just flipped it around with the teeth facing the engine and this time I saw the little nodule of the timing sensor. The tranny went back in much smoother than the first time I put it in. It mated 100% that the first time looked more like 66%.

Some things that I did differently this time that I think helped: Raised the car on jack stands higher. I went out to HF and bought the 12 ton jacks on sale. I raised it 3 notches on that one. It gave me approximately 6 inches more space than before. I still wasn't able to slide the transmission out from under the car on a transmission jack, but I kept it there while I removed the clutch and flywheel from the front. This helped tremendously as I got a lot more room to maneuver the transmission and pivot it in. Since I had filled up the tranny with new motul 300 already, I plugged it with the 30mm 12 pt socket and another socket inside of that to block the hole. It still leaked like half a quart.

I also followed the instructions on the alignment tool properly. Insert into clutch disc first then match up to pilot hole. I didn't follow the torque pattern 100% on the pressure plate as I had very little room with a torque wrench. I just made sure to torque all the bolts to even pressure and the pressure plate teeth were even. The oem clutch replacement and flywheel did not have any unbalance marks so I kind of skipped that part.

Raised the engine up by headers (stock so okay) a 2-3 half pumps to make it even and then muscle the transmission in. Kind of have to visualize what could be stuck and go from there to make it level with the block. I had the hardest time finding the right torque specs. The online service manual was not loading right for me.

If I remember correctly the torque spec for doing the oem clutch replacement:
-flywheel was 65 ft-lbs
-pressure plate to flywheel was 12 ft-lbs
-bell housing to block 35-36ft-lbs (could be wrong here as I could not find this info, used other subaru car... please correct me)
-transmission support 35 ft-lbs(4 to car and 2 to transmission mount)
-drive shaft support 40ft-lbs(online it says 38.4ft-lbs, but I didn't have internet that handy and just guessed at the time)
-driveshaft to differntial 57 ft-lbs(honestly I don't think most people have a torque wrench to fit this one. There is no space on either side to jam a torque wrench in. I used two opposing flat wrenches and jammed one against the metal oil pan cover thing and pushed until I couldn't anymore.
-exhaust nuts (super tight with a extra long 14 wrench)
-exhaust hanger and mid section connection ( tight until it won't go).


Side note: I did not remove the shifter from the top. I tore the shift link dust boot neatly and used rubber cement and a bike patch circle to join it back together. I know this is not the proper way, but it saved probably 30-45mins each way.


Now the car drives like new again. I have to relearn the clutch engagement points now, but everything is smoother and tighter. Also no more whining/whirring. My throw-out bearing made noise at 40k miles, but I ignored it until now when it became noticeably un-drivable (VERY loud noise, shuddering in first at low speeds, and a general feeling of uneasiness that your car is gonna break down any minute now). I thought the crickets were back at first, but it was the T.O.B.

Thanks for all the great community members that helped me troubleshoot and get to the bottom of the issue. Hope this post can help somebody going through similar issues.

TLDR: If your car won't turn over after a clutch job, make sure you install the metal encoder plate with the teeth facing the engine.