1 Lucky Texan

if you own a smartphone, an inexpensive adapter to read trouble codes can be had for under 50-60 bucks. Vpeak makes some, check amazon. Some apps are free like Piston or torque lite. a P0420 code has cat conv in its definition, but often something like an exhaust leak or vacuum leak or rodent chewed wiring or ??? can be the real cause. Never assume a trouble code points directly to a part - it is a symptom. you might also like to read-up over at www.subaruoutback.org - also great folks

next 2 suggestions are trickier; if a spacer at the top of a strut assembly (under the strut mount) is upside-down, it will drag. It is narrower on one side to rest only against the inner race of the bearing in the mount. Or, mount bearing itself is severely failing? You can take the rubber plug out at the top and spray some lube in the bearing....might make a difference. I suppose a rack issue is also in the mix here, maybe others will have ideas?

replaced the rear wiper arm. Grandson ripped it loose. Not happy with the quality of the replacement. Saving the original to try to come up with some approach to reinstall. maybe some thread locker.....?

are those directional? I only ask because, I have a dim memory of some thread about that, seems that it mattered because of preventing or causing fluid to push past the seals? anyway, they should pop-out with a circlip/spring clip on them.

daveT's suggestion is pretty good I think, get an engine from car-part.com , MLS headgaskets and new timing belt system components.

all 4 new tires? all tires must be the same size/model/brand and near each other in wear. Will the car perform smooth, slow tight circles on dry pavement? no jerking/binding?

even here, I miss it as much in winter as in summer. I drove an '81 Honda Civic wagon for over 10 years with broken a/c (no money to fix during those year) - not fun in August....but I survived.

You might investigate a propane/butane mix. From what I have read, not as dangerous as it 'sounds'.....I mean, you have 10+ gallons of gasoline in the car anyway.

year? any pics?

that's the classic symptom of the 'cardan' joint (u-joint) on the steering shaft going bad. To prove it, spray some light lube or even PB Blaster on the joint to see if it (temporaily) gets better.

eh, I can still see its shadow.

hey, you stayed with and got it going. kudos

if you can get specs, maybe there's something off-the-shelf that will work?

Subaru TSB or some such once spec'd the Subaru Coolant Conditioner (relabeled Holt's RadWeld leak-stop) for a generation of cars. That could be the stuff the mech spotted.

the backfiring through the intake sounds to me like the timing is still off.

have the rear bushings on the LCA been inspected?

not a summary, but quite detailed; http://www.subaruoutback.org/forums/66-problems-maintenance/49537-p0420-diagnosis.html

makes it a little more resistable.

I'd have brake CALIPERS inspected. maybe one is not sliding.

if no luck at a yard or car-part.com, try ebay or even a craigslist listing for parting-out a compatible wreck.

welcome, lots of folks here should be able to help.

swapping engine/drivetrain from a wrecked WRX is the 'best' approach for what you propose - dig around at NASIOC.com for examples of swaps. Very time/labor/$$$ intensive you CAN make the present car more fun to toss around corners..

yep, you might get a blink-code. check troublecodes.net - perhaps JDM uses the same definitions for the codes?

interesting - probably explains the Mitsubishi a friend used to drive - it speced ATF for the 5spd manual!

'95 could have a separate Engine Temp Sensor - it may have 1 more wire thant coolant sensor and be located nearby. also, you might consider vacuum gauge testing - compare cold with hot. some gasket or tubing may be failing at higher temps. check system voltage too cold vs hot.