2004 WRX, 226k miles, original engine, trans and clutch. Just changed timing belt, water pump and oil pump as well as all idler pulleys. Ran fine with no weird symptoms for the last 2-3 weeks.
Driving to work tonight, i am getting on the freeway. I'm in second gear and stretched it out pretty far, nearly to redline, then when at highway speed i get in 5th and set cruise at 65. Once cruise is set, i notice some very strange things happening. There is a strange vibration, and i notice my speed going from 65 to 70, then back down to 65, then back up to 70 as the vibration is getting louder. The vibration turns into a knock/tick, and it's not really a consistent sound like what i would think a rod would be. I pull off the freeway and as soon as i push the clutch in, the car dies and check engine light comes on. I try to start it once i got it off the road and stopped on the shoulder, but it just cranked and cranked. It acted like it wanted to start a couple times, but didn't. I plugged in my AP to read the code and nothing popped up.
Now i guess the first step is a compression test, but if that turns out to be normal for a high mileage engine, should i be looking at the clutch as a complete failure, or even throwout bearing? Would that cause this condition?