1 Lucky Texan

P0051 is front (upstream of the cat conv), left side (US driver's side) O2 sensor. dunno about the source of the power to it. might be some help here; http://www.subaruoutback.org/forums/110-gen-2-2000-2004/39012-still-getting-code-p0051-after-o2-sensor-replacement.html

I have a few concerns along these lines; incorrect thermostat may have been installed, IAC hose could have been loose, knock sensor could be bad, idle was incorrectly set too high, the OBD system needs to be read for the check engine light, the used engine you bought may have had bad headgaskets.... there are several failure scenarios we could follow here. you are fighting a lot of variables/unknowns. best approach at this point requires the car be properly diagnosed. I'm not convinced your present mechanic can do this but really don't know. consider a new thread asking for a shop recommendation near your city.

5 spd ? or automatic? any way, if you feel any 'jerking'/binding in the car, like it can't idle thru a tight circle on dry pavement without giving it gas, that could be torque bind. If your tires are all; the same brand, the same model and the same wear level, this could be bad news. You may have some bad transmission parts. If a tire is different, that needs to be addressed - they must be the same. occasionally, bad u-joints will cause issues similar to this. more details about the car would help. Is your mechanic experienced with Subarus?

a gunked PCV valve/hose could increase oil leakage, but probably wouldn't create a leak. here's a nice video; and link; http://forums.nasioc.com/forums/showthread.php?t=965763#9

maybe the separator plate on the back of the engine? Some older engines had a plastic plate notorious for major leakage.

if you find a 'good price' on an 02 with the H6 - you won't care what it looks like. My wife wants a different car and has never cared for how hers looks, but I tell her when she's IN it, she doesn't have to look at it! lol!

well, suppose the system was only 10 oz low? you are now overcharged.

you must have a fan (probably 2) going at idle with the a/c on. That can definitely be a problem. Sometimes people report decent cooling on the highway, warm temps when they are at a stop light. That's because the fan isn't working and clearly there's air moving thru the condenser at highway speeds even with a bad fan. of course, there are plenty of other ways the system can fail. Often, the 2 o-rings at the compressor slowly leak out enough refrigerant to prevent the system from working properly. Or pressure sensors can go bad, etc. read here; http://www.subaruoutback.org/forums/99-do-yourself-illustrated-guides/43428-diy-c-air-conditioning-leak-refrigerant-repair-5-less-15-minutes-less.html

there should be a label telling you the amount of refrigerant. Probably easiest with an empty system to just put in the 22-25 ozs or w'ever the label calls for.

most likely, a low charge due to leakage at the o-rings on the compressor. a pro would recover the refrigerant, swap the compressor o-rings, maybe the guts in the schrader ports, then, evacuate with a vacuum pump, check for leaks by observing if the vacuum holds, then charge the system. they also have 'sniffers' and other methods they can use to test for leaks. You could have a leak in the condenser from a rock, a bad hose, etc. Some people re-charge using refrigerant with UV dye to help find the leak. many people try a DIY approach like this; http://www.subaruoutback.org/forums/99-do-yourself-illustrated-guides/43428-diy-c-air-conditioning-leak-refrigerant-repair-5-less-15-minutes-less.html?highlight=diy+refrigerant+o-rings

good job sorting it out!

anyone have access to TSBs? Service Bulletin #09-38-03 'may' be related to the fuel pump failures and offer some part numbers for sub-divided fuel pump assembly components. Might be able to order a dealer cap or ???

maybe contact them ; http://www.crc-canada.ca/CompanyInfo/hq.aspx

I wonder if the car ever had to be Slim-Jimmed and something is messed-up in there? wait, every door? that is weird, seems like connections and stuff good enough to unlock, would be good enough to lock . yeah, some kinda compromised supply of power???

^^^ yep, plastidip or powder coat w'ever

http://www.jazzyengineering.com/index.php?cPath=21&osCsid=1f7b2iodqgomjq19bkb3e77bt3 http://www.amazon.com/Scosche-FM-MOD02-Universal-Modulator-Satellite/dp/B001QBG614

well, it certainly 'could' = g'ma. interior detailing, maybe some seatcovers (covercraft/katzkin) etc. If she's involved in picking rims, maybe tint, maybe some other items -it'll feel more new-ish to her. At present my adult kids are driving; oldest daughter 1987 (yes 87) Volvo wagon, middle daughter, a 2010 Mazda 3, youngest 2006 Impala their first cars were; late 90s Toyota Camry sedan, 1990 Maxima, 1996 Maxima My kids were thrilled not to be walking....ymmv

dang! yeah, probably need an adapter. best one is hardwired in the antenna cable. I think there was also an 'intermediate' board/connector 'pass-thru' that went between the HU and the main cable. there have been 2-3 work-arounds. someone will remeber all that.

^^^ + 1 for tint, rims (check out Rota for 'affordable' models, also TireRack.com and I think Discount Tire have utilities at their websites that let you load an image of YOUR model car and 'try-on' rims) LED lighting upgrades and xtras. new head unit - prolly new speakers, check Crutchfield.com or any experienced posters that reply here would be good resources too. (I raised 3 daughters, they also helped pay for their cars. I split major repairs with them, but they had to pay for normal maintenance and tires, etc.)

best bet is to pay for a pre-purchase inspection. The mechanic should make a list, and perhaps on the side have a conversation with you as to what needs to be done immediately (maybe a set of tires, or timing belt job) what you can live with ( a little leak here and there, burned out dash lights) and what you may want to save up for (struts or some bushings ) That might also give you some ammo to negotiate a better price. Ask for a shop recommendation in a new thread. maybe someone here knows a place near Burlington.

in this car, are there also some white or other connectors that should stay unplugged ?

Wife's car got a new battery. VatoZone Gold lasted 3 years 9 months, not bad for this part of the country. anything over 3 years is good. But, only had $40 of pro-rated money. Decided to get a Super Start Extreme from O'Reilly's . With a slight difference in price and a rebate (well - gift card) it saves me maybe $5 ,and , the battery is sealed/0 maintenance. Though it may be getting weak/old now, I really like the one in my WRX. I think there's less corrosion because of the way it's vented ? The pos. terminal in the Outback was a mess, I swapped it for anew terminal - AGAIN. Freaked me out for 30 seconds. Didn't want to start until I locked/unlocked it with the remote fob.

I recall that some older soobs had issues with the Engine Temp Sensor keeping the car in 'choke' mode - fooling the ECU into thinking the engine was cols all the time. And that will usually not throw a code. On your car, I think its the 2 wire sensor. Mounted near a one wire Coolant temp Sensor. vacuum gauge probably comes with a few attachments and instructions. Check the web and youtube too.

You may be wasting money running the premium, but I don't see how it could be harmful. I certainly am no ethanol promoter, but I doubt your car would be harmed by using the regular with 10% or w;ever ethanol.