Numbchux

I know STi turbo head gaskets are used on the SOHC 2.5 all the time, I would think WRX would be the same. Timing change would be negligible, compression might be noticeable.

WRX 2.0 head gasket should work just fine. Everything else is the same as SOHC 2.5. Very easy to get parts with that little bit of information.

use your VIN on the parts site, it'll only give you one option. Or, look at the plate on the LH strut tower in the engine bay for the original complete engine code.

If anyone has any insight, or, I'll just document what I find in case someone is looking in the future. My mom's 2012 Impreza 2.0i Premium. 216k miles, original engine and CVT. Had the torque converter solenoid fail last summer, and the fluid was a bit brown, so I did a drain and fill then (probably 190k miles), and we did another at about 80k, when I was working at a dealership. The AT Oil Temp light was flashing one day, I scanned it about 2 days later (no lights on) and it had a stored P0841, as well as a U0100 (CAN signal error), C1431 (AT abnormal), and C1422 (VDC Interrupted). From the Subaru FSM: First 2 steps in the diagnostic procedure is to check the condition and level of the CVT fluid. I think she's going to have another drain and fill done (she does not live locally to me, so I probably won't see the car for another couple weeks). And then there are a few tests using the SSM to check the pressure readings from the sensor under a few conditions (Idle in park, 3k rpm in park, torque convert stall at WOT). Beyond a fluid related issue, the procedure basically ends with the sensor, wiring, or transmission causing the fault. The secondary pressure sensor is externally mounted, threaded in towards the rear of the left side of the transmission. By her VIN, part #31878AA020, with an MSRP of $148.17

I don't quite follow what you're doing. But, the low range gearset is on the input shaft of the transmission. The EJ cases are cast with the cavity for the gears, but they are not machined out for the bearings and such. It would take quite a bit of precision machining to convert a single range case to dual. The 4WD versions have a very different output shaft/front pinion arrangement. You could use a FT4WD front pinion gear in an EJ output shaft, and then have the locking center. But if you don't care about unlocking, it would be far easier to just weld the EJ center.

The fact that it's felt in the steering wheel has me thinking it's not the transmission. I just replaced a CV axle with a completely failed inner joint, and it could not be felt in the steering wheel any more than anything else (it shook the whole car....). I've been chasing this vibration for years, and because it wasn't felt in the steering wheel, didn't even occur to check the front axles. Boot was fine, and it only happened once driven at least a few miles. Does it change at all when on or off throttle? Brakes? Pull to one side more than the other?

That's puurrrrdy

The ECU, and emissions system in the car is not expecting an EGR. So you are just keeping it factory. Blocking off EGR on a system that had it is different.

Yep, Take the wire off the starter solenoid and run it to trigger the relay.

I've put a hot shot relay in a couple subarus with no trouble. As long as it's triggered by the factory switch, it should all be fine. The system doesn't know if it's directly triggering the starter solenoid, or a relay. It's possible that the original problem was a failing neutral/range switch or wiring to it, and you are now getting a second symptom.

Should be a yellow tag on a battery cable with instructions. But yes, if the battery is disconnected, the parking lights will flash. Ignition "ON" and press that button for 1 second resets it.

A lot of variables. Be more specific with your questions, and you will get more specific answers. All EJ engines share essentially the same basic dimensions. So they will all physically fit almost identically (with the exception of the last few years of the EJ253, 2010-2012 or so, where the motor mount configuration changed a bit). 2.2s were made 1990-2001. So the difference comes in the electronics, which can be changed. But ASSuming you want to use the ECU and wiring from your donor car (cheapest option), the rule of thumb, is the older ones are simpler, and the newer ones are more complex. 1995 (for the 2.2) added OBDII, which makes them far more easy to diagnose, as any off the shelf code reader can connect to it. But much newer than that adds fuel tank sensors and stuff that will be hard to replicate/bypass in the new chassis, so you will likely always have trouble codes.

IIRC. The viscous LSD unit is separate from the spider gears. If you were to cut that shaft in half, it would be like an open diff.

Yes, both fans should cycle in test mode. I would use a test light or multimeter to backpin the fan connector while in test mode and see if it's getting power. Might just be a failed fan. The fans really only make a difference under 15-20mph. So with those symptoms, I would question the gauge reading. Might be worth plugging a code reader in and seeing what temp the ECU sees (separate sensor), and/or using an infrared thermometer to test. Might be a grounding issue causing both problems....

quick google search turned up this

We saw many at the dealership. Causes a misfire. Wasn't uncommon to have cars towed in from other shops that had thrown a coil, injector and more at it trying to "diagnose"/repair a misfire, and it was a dropped guide. Never heard one make a noise.

Knock knock, your new engine is calling. I bet you have very little oil pressure, as it's all blowing out past your rod bearings. Thicker oil and/or a high volume STi oil pump might buy some time. If the guide around the crank pulley is too tight, it will rub the text off the back of the belt. Was this clearance set correctly? Mitsuboshi makes belts for most Japanese OEMs. They do not sell them through the major parts stores, so many people don't realize they exist, but if you start watching, you'll see their name, or logo, on most belts (just did one on my Honda Odyssey yesterday, the original belt said Honda on it, but had the Mitsuboshi logo). Gates used to use quality Japanese bearings, but started phasing lower quality ones in probably 10 years ago, becoming increasingly more common. You don't have to search very hard to find wrecked engines due to Gates kits. With a little homework, it's not hard to find quality Japanese components from reputable sellers (NOT Amazon or eBay, lots of counterfeits) for a reasonable price.

Just looks like an old belt, to me. Certainly time to change it. But if it were really rubbing, it would be far more badly damaged. That just looks like the scuffing from the crank guide. Aisin tensioner, Mitsuboshi belt, and Koyo or NSK idlers only for me.

The tensioners I've had fail were entirely unaffected by temperature. I supposed it's theoretically possible that it's only failed a little bit, and it might change as it warms up, but I would think as soon as it cycled through it's range (which is what the noise is, the piston bottoming out and the housing hitting the block), the fluid would be gone, and it would be spring only.

Rod knock comes from connecting rods, not pushrods. EJ251 is not a rotary engine, so they absolutely do have rods.

Sounds like rod knock. Piston slap goes away as the engine warms up. Timing belt tensioners are unaffected by engine temperature. Rod knock gets worse as the engine gets hot. Put a real oil pressure gauge on it, and see if your oil pressure drops as the noise happens....

Speed and neutral signals both help with drivability, preventing the engine to stall when coasting and such. Not a major change, but super easy to hook them up, so just do it. Yes, both fan signals are ground signals to trigger relays.

Maybe try a different dealership. Also, spend as much time on the freeway as possible during the consumption test. I know when I worked at the dealership, we would have claims denied (by Subaru), and then a few days later, SOA customer service would call us and have us Goodwill a repair. So a call to them would certainly be an option. Quick google search turns up 1 (800) 782-2783

Blinking CEL, Test mode? My first EJ swap cranked a lot before starting. I didn't have the start signal wired to the ECU (12v while cranking), this changes the enrichment (choke) while starting. I bought a dry cell battery and a block heater, as it would struggle to start so badly in the winter....then I hooked up one wire. But I think I had a code for it.

Yea, technically here in MN it's a "Prior Salvage". True "salvage" stamped titles cannot be issued plates. The inspection to convert the title from "Salvage" to "Prior Salvage" has nothing to do with safety. They just want to see the receipts for the major parts purchased (to verify that nothing is stolen). Whatever the verbiage. Once it's totalled, no warranty of any kind applies. Recalls, however, still do (had the Takata removed from our '04 VDC).