Greenmamba

Subaru dealers in Maidstone? Failing which, give Red Oak garage a ring? They are not specialists, just good mech's.

Alarm/immobiliser probably.

You Tube says it's private, unable to view.

Sorry to say Stewart, I'd think about scrapping it. Costs to properly repair will be more than the car is worth. You've likely got bent valves and god knows what else.

What stuartie said. Ultrasonic detector for internal alarm.

Yep, cross bars.

@Delek - the service invoice/receipt might state what they used. You do know Subaru atf level is checked with the engine running, in Park?

Do you know what atf fluid was used and are you sure the fluid level is correct?

@AnnaOzNoted. have you checked the cell battery in each key/remote? It is unusual for the car battery problems to cause issues with the remotes. And have you sorted the brakes problem mentioned in your first post?

@AnnaOz - alternators shouldn't heat up to any significant extent nor snap belts. Is this a recent development - have you had this problem since owning the car? Anything to learn from recent MOT's - advisories etc? Also, what is the problem with the keys?

If you pm me your email I'll send you a Word document on the M30 alarm codes/settings etc which might be suitable for what you have. The other thing which might be the problem is the aerial wire for the car's receiver (which gets the signal when you push the button on the key) may be dislodged/unconnected. If this is so you'll have no joy regardless of the keys problems.

Did they ever work? Confirm you've checked the batteries? Do the remotes disable the alarm/unlock the car?

Tyre/wheel balancing off maybe? Wheel bearings usually start with a droning noise which gets progressively worse. Does the sound change when turning left or right and if so is it direction-dependent?

Very nice

Subaru auto transmissions must be running, in Park. If you have been checking with the engine off, the marks on the dipstick will be way off; you may have very low fluid which could explain the noises.

Is the transmission fluid at the right level, checked with the engine running, in Park? Does the noise change if turning right or left? Quite possible to be wheel bearing all else being equal.

@GGMan - have you tried https://partsouq.com/en/catalog/genuine/locate?c=Subaru Put your VIN number in, should bring up your car.

eBay?

OBs have 2 of those, one front and one back. Not sure same applies on Imprezas but worth checking?

Sorry, not a clue! I've never had to use the guide.

If your alarm is the same as mine this might inform. Sigma reprogramming quick guide m30.pdf

There should be a keypad inside the fuse flap, near the drivers right knee.

Only one kind of virgin I'd use.....

2008 will be costlier running costs and tax but assuming service records support it, more reliable. Cam chains on this engine are non replacement items unless faulty so no worries there about them not having been replaced. To some extent, it depends on what you plan on doing with the car. Drive both and see what you think - big performance difference for one.

I'd avoid diesels, particularly Subaru. Early models were prone to crankshaft failure amongst other faults.