1.7 @200k miles ish.
Cold morning: Full choke, turn key - fires almost instantly in that snow-covered volvo way.
Car idles a little unsteady but not concerning.
Once engine is warm and I'm off choke this happens:
Past 50% throttle over 3000 revs the engine gives a nasty continuous grating noise, I'm not sure if its preignition or detonation or a loose component,when the grating gets noisier it does seem to sap power e.g. more accelerator(past halfway) = less power.
To me it sounds like a really OOB thing on a shaft with loose bearings ragging itself to bits?? like a worn viscous coupling, doesent "roar" though, it's grating.
