Numbchux

The biggest difference will be that the Outback struts will give more clearance for larger tires. The overall strut is longer, and the spring perch is higher up on it.

Yes, the water pump will swap. The exhaust will swap (you might have to swap oil pans for clearance). I would do some research before spending any time on it. Confirm (one way or another) that the 06 is VVT and 05 is not, and what that means for the swap. Best practice is to keep the intake manifold, wiring and sensors that match the car (hopefully you got it with the disassembled car).

I believe '05 was likely EJ251, and '06+ is EJ253 with VVT. So the heads are likely different. I think it's possible to run a 251 on 253 controls, but you'll likely have trouble codes (which you may be able to surpress). And yea, they moved the cat closer to the engine in 06, so the manifold is a different shape, and I think that's the reason for the water pump change, as it changes the routing of the lower hose, slightly.

Alright, so you have a complete EA81. Decent engine. Here's an old writeup about using EA82 SPFI on an EA81. https://www.dropbox.com/s/k4kdbpaclc6sko4/EA81_SPI_guide.pdf?dl=0 As for swapping to an EJ. These guys have been doing it forever. It's not cheap, but should solve basically all the fitment issues. https://smallcar.com/vanagon/subaru-vanagon-conversion-parts/subaru-vanagon-parts-kit-4spd-vanagons-and-syncro/ Or, from the company that made the adapter you have: https://www.kennedyeng.com/subaru-vanagon

Yep. My first step would be to inspect, clean and lubricate all the moving parts in the brake system.

Came here to post what @idosubaru posted. I also want to add if the vibration changes one way or the other while braking?

Yep, the term is frequently used interchangeably. The front one on a 2003 2.5 is installed right in front of the first cat, angled up along the RH side of the front of the transmission.

Typically referred to as an Oxygen sensor, and listed that way in aftermarket listings. But an Air/Fuel sensor (Or wideband) sensor can detect a wider range of mixtures with more accuracy than an Oxygen sensor. Modern cars (in the last 20 years or so) generally use AF sensors upstream to monitor the fuel mixtures and adjust how the engine is running, and just O2 sensors downstream just to monitor converter functionality.

You don't have time to do an EJ swap, but you do have time to reverse engineer someone elses bastard and start over? If time is your concern, an EJ22 swap will take a lot less time then figuring out what you have, and redoing it. And the results will be 1000% better. This is not debateable. Yes, you'll have to spend $1k or so, as nothing you have will help. You do not have EJ heads on an EA81 block. I'm the first to say "anything is possible", but I really don't think that is. It's certainly so incredibly far beyond reasonable that nobody would have done it. You cannot put one of these: Here:

Well, then it's not covered. That said, it's not a death sentence as long as you keep an eye on it. I've also heard of people switching to 5w30 with considerably reduced consumption.

If it has under 100k miles, take it to your nearest dealer for an oil consumption test. It likely is still under warranty.

Other control arms can be used, although the inner bushing is different, which poses problems with the stock crossmember. That said, those other control arms wouldn't change anything with the sway bar mounts....

I disagree with that so much, I deleted it when I quoted your post. EJ22t is definitely not the best Subaru engine ever made. I've owned several high mileage 00-04 Ej25s. Never had coolant leak out the block. They all leaked oil externally. These use the exact same head gasket as the 05-09. Now, of course, we're talking about ~20 year old engines. There are soo many variables in maintenance and care that have a bigger effect on the future running than any design changes. For example, I have an '02 Outback H6 that's been clearly beat up, neglected, and left for dead, and it has a dead cylinder, at 130k miles. And my daily is a '00 EJ25 with 355k on it, that runs beautifully.

This is usually true. The dealership I worked at actually did use 770 gaskets, and had a couple really good techs. But, having plenty of issues meant high turnover (myself included) and some pretty novice guys in the shop. But, having worked in auto parts here for about 15 years, I have dealt with most of the local independent shops, too. And there's only a couple that I would trust to torque a lug nut correctly, much less do head gaskets. What I'm saying, is either one could go either way. About the only thing you can verify with 100% certainty, is to ask for the repair invoice that shows the part number of the gaskets that were used. If they knew enough to use the correct gasket, that's a very good sign.

Did you remove the engine or transmission to do this work? No part of the axle is spinning? like, maybe just the inner cup.....

That Moog one is $22+shipping OEM is $35+shipping https://www.subarupartsdeal.com/parts/subaru-tie-rod-complete-gear-box~34140fc000.html 10 times the quality, for less than twice the price.

Don't worry about it. The original post is almost a year old, and the poster hasn't logged in since March. I don't think it matters.

Sure doesn't make sense that the knock sensor code would effect the idle. But, it'll cause it's own issues. Might as well fix that issue first. Inspect the coolant temp sensor wiring while you're poking around.

Moog is just another sticker on Federal Mogul parts. Suspension companies buy and sell from different suppliers. Some are better, some are not. But there's no consistency.

I believe that engine should be speed density (MAP sensor, no MAF), and therefore shouldn't be that sensitive to leaks before the throttle body. IAC is built into the throttle body, no separate hose for that. What did you disconnect/remove to access the plugs? I generally remove the washer reservoir on the LH side, and airbox on the RH. The throttle cables (main and cruise) run right over the plugs on the LH side, you sure you didn't shove them out of the way and they got hung up somewhere? Any trouble codes? Confirmed, or pending? What does the TPS signal and coolant temp look like? How did the knock sensor wire get damaged? Was there something tugging/chafing on it? The coolant temp sensor is in that area, too... The symptoms kind of sound like a sticking IAC valve. Although I don't think I've ever heard of that on these before. And the timing would have to have been a complete coincidence, which is unlikely.+ I do agree that Iridium is not ideal for your car, but shouldn't cause any problems.

FB engines got the timing chain. 2011 in the Forester, 2012 Impreza, and 2013 Leg/OBK. And it was those early ones that had the class-action lawsuit leading to extended warranty coverage to get a new shortblock. I believe the lawsuit covered through MY 2015, but many newer than that were getting warranty shortblocks for the same reason. The Foresters did not have an oil level sensor/indicator. So if the owners did not check their oil (maybe I won't if I ever have a new car, too...), the first indication was low oil pressure warning light, at which point, it's really too late. So it's not uncommon to see Foresters with blown engines. The others did have a low oil level warning light, which helped, considerably. My mom's 2012 Impreza is knocking on the door of 200k miles, with the original engine. She has to add about 1-1.5 quarts between changes. Hers is a salvage, so was not eligible for the extended warranty, but I don't think the consumption would have been enough to get a free engine, anyway.

Factory 15" wheels will not clear the factory brakes on that car. You can swap to the 276mm rotors and matching calipers. You can grind the calipers (I've done this twice). Or you can use a gravel-style aftermarket 15" wheel (Team Dynamic, Braid, Method, Sparco, etc. etc.).

When I worked at the dealership, we frequently handed out the gasket for the duty C solenoid, a little pipe in the tailhousing, as well as the clutches, housing gasket and output seal. I don't remember exactly the symptoms, but I know the fluid from the solenoid and clutches could leak down and cause some symptoms (usually eventually worn clutches). If you want it done right the first time. Likely that whole list from Subaru, as well as some new HP fluid and OEM filter.

Summit probably isn't your best bet for parts for this car. Most of us use RockAuto.com these days. It can sometimes be a little hazardous finding parts for these cars, as the naming structure isn't terribly clear ("GL" was used on many body styles, with overlapping years), but '88 and '89 are the easiest, here in the US. But when you can, look for measurements and verify them. Also, in 88, yours should be an EA82, which is usually listed as an OHC engine, (EA81 was OHV, but is a different body style with very few parts directly interchangeable).

I much prefer SOHC ('99/00+) 2.5s to the DOHC. They're more common, simpler, and the standard HG failure is an oil leak, not really a big deal. I know you said -2003, although I'm not sure why, there's no major change on almost any model between 2003 and 2004 (Impreza got different lights...). 2004 and 2005 LEG/OBK could have the EJ259 california engine, mechanically very similar to an EJ251, but completely different electronics, including drive-by-wire. These are not necessarily problematic, but they're rare, which can make things difficult when it comes to diagnosis and parts replacement. I wouldn't turn down the right deal on one, but it would give me pause. I love the EZ30, I have 4 01-04 H6 Outbacks, including both of our daily drivers right now. By far my favorite Subaru (for a daily, anyway).