Fairtax4me

How old is your brake fluid? This is a good time for a flush. Find a rubber plug the correct size to fit in the end of the banjo line. When you unbolt it from the caliper plug it off to avoid fluid loss.

Some MT cars have a manual key cylinder lock release which prevents turning the key back to the lock position and being removed without pressing the button. Subaru doesn't have that, but lots of other cars do, so the parts yard listings usually have to specify which trans type. Remove the cylinder and have a local locksmith rebuild it. Usually under $30 for new pins and tumblers and a new key cut to fit.

Are they blaming the control head because the new compressor will not engage? The control head doesn't directly control the compressor, so no chance of electrical shorting/ damage from a failed compressor. There are always possibilities for electrical damage, depending on how the shop goes about trying to diagnose a problem. Paper clips and jumper wires were acceptable to use years ago. Newadays everything is controlled by a computer in some way or other, and computers don't like people poking around with test lights and such. Even though they may have push buttons like older cars, the control heads in these are digital. They send signal to another computer, and that computer tells the compressor to engage. There are multiple switches, relays, and fuses involved. A failure of the control head is very unlikely. I would want a second opinion, and I would want to see the old compressor to see if its full of metal shavings.

Jerking/bucking when going straight could be due to damaged transfer gears in the tail housing of the trans. I didnt catch the year of the car in the first post. 99 had an issue with a snap ring popping loose and getting snagged up in the transfer gears. Any chunks from those typically stay back in the tailhousing and dont make it to the rest of the trans. Only way to run FWD with a manual trans is to weld the front pinion shaft to the countershaft. The VW conversion guys have a fabricator who makes a bolt on coupler to go in place of the VC rather than welding. They AWD trans and convert them to FWD to use in buggies because the AWD trans is so much more common. The coupler costs a couple hundred $$ IIRC.

There's no fuse for gears in a manual transmission. The transmission is purely mechanical. Either the gearshift is not moving all the way into the gear, or something internal to the transmission is damaged. I'm betting on the first since transmissions don't break if the car isn't moving. With the engine not running try shifting through ALL of the gears, then see if the shifter feels the same with the engine running.

Old brass and copper radiators often had ground straps to help keep away galvanic corrosion. New stuff ain't got them no more.

Can you post a picture of the plug? Most machine shops do not check for valve issues unless you specifically ask them to. If you just ask for a re-surface, that's what they'll do. The process for checking cracks, leaks, and valve seat issues, is more involved, and you'll typically be charged $20-40 per head for that. Burned valves are most often due to incorrect valve lash clearance. Pull the galve cover and check lash clearance on that cylinder. If any valves have zero lash the burned valve theory may be correct. Seafoam/ intake system cleaners only really work if the cylinder is actually firing. The compression in that cylinder is too low to ignite the AF mixture and burn away the oil and carbon in the cylinder, thus the buildup of crud on the plug.

Yeah you have a compression issue in at least one cylinder, possibly two. You can hear the quick spike in the starter speed at every 4th stroke.

Should see at least 160 psi compression. 180-200 is considered normal but with the high mileage you may have a bit lower. The bigger deal is that compression should be fairly even across all 4 cylinders. You can tell alot about the compression of the engine by turning the crankshaft by hand with a breaker bar and feeling the compression in each cylinder build as you turn the bar. You should feel compression building each half rotation of the crankshaft. It takes two full rotations of the crankshaft to bring all 4 cylinders through their compression strokes. If you count the compression strokes you can tell if one or several cylinders are not making compression. You can also tell alot by running the starter (via turning the key), if you know what to listen for. If the engine spins smoothly, and doesn't chug-chug-chug-chug as the starter is running. That's an indicator of no compression in any cylinder. Here again, if you can count the "chugs", these are the compression strokes for each cylinder. These should be evenly spaced for as long as the engine is cranking. If you count only two or three chugs, with a gap between, that's an indicator of low or no compression on only one or two cylinders.

The bucking is probably just the "Subaru Jerk". These have alot of driveline and lots of places where a little bit of play adds up to a jerky ride if you're not used to the way the car drives. Removing the rear driveshaft and not being able to move says the VC center diff is in good shape. It's not a true open design, but it does have to heat up before it will transfer drive torque to just the front or rear wheels. It has to heat up ALOT before it will make the car drive in only FWD. The mainshaft bearing flings off a lot of fine metal flake. It doesn't hurt anything else unless the bearing is extremely bad. It will pop out of 4th and 5th gear if the bearing is worn badly enough to harm other parts of the trans.

Rest system pressure is around 90-100 psi. A little more on a hot day. The compressors on these will turn on with as little as 30 in the system. The older cars will actually pull 15" vacuum on the low side, 60-80 psi high side, if the charge is low enough. You won't get cold air, but the compressor will run. If the compressor ate it you'll find metal shavings in the discharge line from the compressor to the condenser. This will mean replacing the compressor, condenser, the drier and possibly the evaporator core, then flushing all of the hoses to remove all the metal from the system.

With the engine off spin the compressor hub by hand a few times. There should be some slight drag, but it should spin smoothly with maybe a bit of a "lumpy" feel like you would expect from compression. If it feels very easy to spin, notchy, scratchy (like it has sand in it), compressor is probably kersploded inside.

Put a post in the classified. Plenty of people parting out cars from that era and those are easy to get to.

Scrap yards / junkyards do this sort of thing all the time. Might try calling a few in that area and see if they can package it for freight shipment. Also ask if they have a preferred carrier.

The innernet suggests its a 17.8x2.4mm rubber o-ring. Stop by Napa with the pickup tube and see if they have one that fits it.

Subaru recommends you start the bleed procedure at the front and cross cross. I've always had good luck starting with the brake furthest from the master cylinder and working to the closest. You could still have air in the system. It's very hard to get all of the air out if the system goes completely dry. When the seals pop out of the rear wheel cylinders you're better off to just replace them. Did you replace both cylinders as well as the shoes? Incorrectly adjusted rear shoes can cause a low-pedal condition. After a few dozen pumps of the brakes the self adjusters can bring the shoe adjustment closer to the correct point, but may not get them all the way. Brand new shoes should drag pretty good when spinning the drum/wheel by hand. It shouldn't be difficult to spin, but you should be able to hear them drag on the drum. After the first drive they'll be broken in pretty much perfectly.

The ECU will hold idle up some when coasting but should only be around 900-1000 rpm. The highest high idle you should ever get is 1750 rpm, but that won't be unless its well below freezing outside. Idle higher than that on a warm day says either the throttle is partially stuck open, or the Idle Control Valve is misadjusted.

The OBD2 plug should still have power with the key off. I'm not sure of any wiring that would be damaged from below by a chunk of road. Fuel pump relay is grounded by the ECU. Need to double check fuses for the ECU. You might also check for damage to the passenger floor pan.

No way to test it outside of the car. Not without some special tools. Did you take the old trans back for the core already?

FWIW, your posts are impossible to read because you don't use punctuation or proper English. You asked for help and we offered what we could. Good luck.

The groove in the V power plug helps to direct the spark, it won't cause a misfire. Have you pulled the plugs to check their condition? Possible the number 4 plug is damaged or fouled.

Not the diff. Diff problems will make noise that is wheel speed dependent. The Mainshaft ball bearing is worn.

Is it a 4 or 6 cylinder?

Your crank is 90° off. Subarus aren't timed at TDC. It can be done, but its a PITA. The correct crank timing mark sets the pistons at half stroke, 90° off TDC. The notch marks on the cams set them 45° off TDC. Line up the notch on the reluctor tooth on the REAR edge of the crank sprocket with the notch in the crank sensor housing. Keyway slot should be straight down. Arrow on the face will be at 3 o'clock.

It thats the case, either your compressor pooped itself or the expansion valve blew out. Is the compressor hub turning at the same speed as the pulley? If the clutch is slipping a little that will cause some problems but it should still show slightly different pressures between low and high. What kind of noise is it making?