Fairtax4me

Do compression and leak down tests before pulling heads. Low speed misfire is usually a spark plug or wire issue. Could be injector related, got any BG 44k?

Get a boot kit from Subaru. The aftermarket turds fall apart in 6 months. If the axle cups are painted green they are OE Subaru axles and you should try to keep those if at all possible. Ahh, no vehicle lift needed to remove these engines. The 99 and later engines have 4 extra bolts in the bellhousing but are still way easy to pull if you need to. Best part is the wiring. Look on top of the bellhousing on the passenger side and you'll see 3 big plugs and a few small ones. Unplug those and all the engine wiring is unhooked. Engine pulls out with all the sensor wiring in place! No fidgeting with connectors for 2 hours trying to get them all unhooked.

Many newer cars have a main fuse in the underhood fuse panel, usually rated for about 100 amps maybe more, and the main fuse handles all power that goes into the electrical system of the car (except for what goes directly to the starter). If the car has a main fuse, and it is blown, nothing in the car will get power.

Gotta go with the dead battery theory. Do you have a voltmeter or even a test light you can put across the terminals to see if the new battery has a charge?

I had to go check because I wasn't sure, but you're right those are way cold. I didnt know before that the racing plugs last digits are the heat range. On standard plugs the last two digits are the gap size, and heat range is the 4th or 5th digit depending on the plug. Those would be way too cold to run with a stock ignition setup. They're 6 points colder than the stock BKR5E-11. The Ej engines do tend to run on the lean side. Subaru has the fuel mapping lean for economy reasons, but the DOHC 2.5 seems to run a bit more lean than the others, especially in the upper RPM range. The heads flow very well and the big displacement needs more fuel than the tuning allows. So the spark plugs tend to come out white when they get changed. White powdery deposits are an indicator of hot combustion which is usually due to lean A/F ratio. With the increase in amperage across the plugs that would increase heat generation, so it seems like that would cause them to wear quite a bit faster. And a wasted spark system fires the plugs twice as often, that which leads to shorter plug life even with a standard ignition system. What kind of life do you get from a set of plugs running this plasma ignition system? Have you modified a wasted spark system to use this before?

Just needs extra hand (helper) and an Ej engine can be lifted out of the car by hand. Don't have to be crazy, just able to lift about 150lbs. A little less if its an automatic. Piston slap is harmless. Makes a little racket when the engine is cold but generally goes away once warm. The 2.5s are prone to it because of the longer stroke, but they still go 300k miles just slappin' away.

Yes, I probably would have done plugs and wires first (especially if you don't know how old they are), but when the knock sensor sets a code that pretty much means it needs to be replaced anyway. It could have just been poor connection or faulty wiring, but it seems like about 99% of the time it's the sensor at fault. Very common problem, and a bad KS makes a huge difference on these cars.

Ok, flashing CEL indicates a current repetitive misfire. Whatever codes you get post them up here (exact codes not just the definition) and we can help you weed through them and figure out what to address first.

Need more info than that, help us out here. Automagic or manual transmission? How many miles on the car? Is the engine hot or cold? Does it stall every time or just sometimes? When was the last tune-up?

What setup are you using to control this plasma ignition system? Those plugs are 1 step hotter than a stock plug for Subaru. With a "typical" ignition system pinging may be an issue due to the extra heat withheld by the plug. Ejs tend to run lean anyway so this could lead to other problems. (Internal engine damage)

The fuel fill issue is probably not related to the stumbles. There are several large diameter hoses and a small air filter canister back near the fuel tank/filler under the right rear corner of the car. If any of those clog you will have problems with the pump cutting off while filling up. There is also a valve in that area they call either the drain valve or vent valve which is supposed to allow fuel vapor through to the charcoal canister while filling, if the valve is clogged or corroded internally it will cause problems. The aforementioned air filter has a hose that vents out to open air, it makes a good place for a spider or moth or other nesting bug to call home for the winter. Unless the Check engine light is on you probably won't have any codes stored. There may be old codes but its usually best to erase them and see if any come back to determine what current problems there are. Misfiring/stumbling is usually spark plug/wire related. Obd2 is still the federal standard. Although they have expanded the diagnostic capabilities with the most recent CAN-Obd2 (Controller area network) versions that include more than just engine emission systems, the basic underpinnings are still the same. Torque app works with all current Obd2 protocols and will work with your car just fine. The cheap $50 scan tools are useful but a lot of them don't have code definitions programmed into the scanner, so you just get a code and have to look up the definition yourself. Innova makes some really nice scanners that you can get on amazon for about half of their retail price. But they're in the $65-150 range last I checked.

Have to have a scanner. No way to "blink" the codes on post 95 vehicles. You can go to most auto parts stores and get codes read for free. An inexpensive and effective option if you have an Android smartphone, you can get an app called Torque, and order a Bluetooth adapter to plug into the car. The app allows you to read codes, log live-data, and email or post it to the various social websites (and more). I think the adapters are only $15-20. There is also an app for Iphone called Blue-Driver that works very well, but the price for the app and adapter is like $100 now. Used to be cheaper, dunno why they jacked up the price so much.

Added better info to original post. Just posted the link in case anyone else has strange O2 sensor readings on an OBD2 scanner. It does a good job of explaining the difference between the two major types of oxygen sensors.

I seem to remember reading somewhere that they are different, but I'm not 100% on that. Maybe check opposedforces.com ? What year Forester?

Whatever you do, don't buy heater hose to replace it. You'll be replacing it again in like a month. (You probably know that but just in case someone else has the same problem and doesn't know.) Emissions hose only.

There's always something you forget. Good thing about digikey is they're usually pretty nice about adding stuff to the order if you give them a call. They do package and ship REALLY fast though, so sometimes they can't do it.

I bought a heavy duty "electronic" flasher years ago for the same reason, but the one I bought was still a bi-metal strip style flasher. Clear plastic case an everything. Couldn't figure how they could call it "electronic" when it's still an analog style flasher. Anyway, it didnt work. If you're gonna buy one make sure it has the right guts inside. Resistors are pretty easy and you don't even need multiples. You can wire in one resistor right at the flasher and get the same effect. You would have to wire another resistor at the hazard flasher as well since Subaru uses a separate flasher.

My other thought was to just fill the whole thing with epoxy.

Cheap fix. Must mean you have a good shop. Glad to hear its fixed, and thanks for posting the cause.

Additional info required: A while ago (like a year or more) there were some threads floating around about O2 sensor voltage readings in the 3+ volt range on diagnostic scanners. I don't recall there being a clear answer as to the reason at the time. I have had some O2 sensor issues recently so I went digging for info and basically found that the reason for the trouble was that I bought the wrong type of sensor. I bought an O2 sensor, when what I needed was an Air/Fuel Ratio sensor. The problem was on a Toyota, but the same principles of how the sensors differ apply to every brand of vehicle. The link below comes from a website we use in school, and has tons more info about various sensors and their functions, as well as dozens of other tech articles that can be useful during diagnosis of a problem. What my issue boiled down to is the ECU was getting a reading of incredibly lean mixture from the O2 sensor. Because on an O2 sensor rich = high voltage and lean = low voltage. but wih an A/FR sensor its the opposite, rich = low and lean =high. The ECU would add more fuel and get a rich voltage back rom the sensor,except the ECU is programmed to read high voltage as lean, even though the sensor was responding as it should. And so the cycle repeats itself until the ECU can no longer adjust, which in this case pegged the Long Term Fuel Trim at 44.5%. But back to the point, if you get oxygen sensor voltage reading in the 3V range on a scanner, its because you have an Air/Fuel Ratio sensor, which gets supplied a reference voltage of 3.3V from the ECU. The sensor then bumps up (if lean) or bumps down (if rich) the return voltage signal back to the ECU. Some ECUs convert scanner output to a normal O2 sensor output voltage to avoid confusion, but not all. Be sure of what you have before purchasing a replacement sensor. http://www.autoshop101.com/forms/h37.pdf

Because aftermarket axles have very loose tolerances that allow the axle housing to rock back and forth a bit with the vibration/power pulses from the engine. This causes a small vibration to turn into a large one because the axle sort of hammers on the inner joint. One way to test the axle is to let the car roll forward slowly, about 6-12" usually does the trick, with your foot still on the brake. The vibration will fade away once the axle is moved to a different position. It may then come back on its own without moving, or you may need to roll forward another few inches before the vibration returns. Known cures are to replace the axle with a rebuilt Subaru OE axle, or quality new after market axle. I think EMPI is the only recommended aftermarket brand. This is a commonly covered topic so there should be plenty of info about which axles to use here on the board. If your old axle only had a split boot, ask the shop to put new boots on it repack the CV joints and put it back on the car. If the axle was making noise (clicking) order a rebuilt one from FWE (only rebuilds Subaru axles) and send in the old Subaru axle for core credit.

Unless it blew chunks the transfer bearings are easily replaceable.

You haven't tracked down the beeper and unplugged/destroyed it yet?! Does the dome light stay on while you're driving? That I think would indicate if its a door switch problem. Otherwise it's probably a poor contact or short in the switch on the lock cylinder.

Probably a poor ground. Usually due to corrosion in the bulb sockets.

Sounds like a backing plate fell off. Shouldn't be hard to find the source if you jack up each wheel and spin it by hand.