2000 Impreza L engine problem

While driving home last Thursday night my Subaru started to die.
Car has 235000 on odometer.
2.2 litre auto transmission
New timing belt,waterpump,camshaft seals and all other seals done back in December.
Car never used oil
Ran perfectly until last Thursday.
Driving down little hill around 40mph and I started to apply gas pedal and it started shuttering and making a metal on metal sound.
I pulled over and popped hood.
Most of the engine rattle coming from airbox side on top.
Oil is perfect on stick
No oil in antifreeze
No oil leaking anywhere on top or underneath
Oil on stick feels cold like it wasnt circulating.
I was told to take out front sensor on front cat.
I done that and still no difference.
So much for a plugged cat!!
The #1 cylinder when I took plug wire off was full of oil coming from inside the boot.
Any ideas what it might be??
I was told by someone that the chance of oil pump going in this impreza is slim.
Could electronic ignition have gone on my impreza or engine gone??
Thanks!

drain your oil and check for any metal in your oil. sounds like you might have spun a bearing or its bottom end related. not sure with out looking at the car. pull your timing cover off and check your hydrolic belt tentioner. if that got weak the timing belt could have slipped and your valves might have just smash against the piston not good!

The oil on plug was likely caused by spark plug tube seals that have a leak, the nose is hard to tell as others has said without hearing it in person. With the engine cold, take a 22mm or 7/8 socket and rotate the engine over moving it back and forth. If you have spun a bearing you will be able to easily to hear and feel it. The oil sample is a great and fast way to check for any bearing or other bottom end issue. Even with the mileage, I highly doubt that you have spun a bearing. If it didn't get hot... not likely. Your 2.2L has hydraulic lifters, possibly one has collapsed or is stuck in the bore.