Quote Originally Posted by jdclayton View Post
Would I only notice the issue at idle, or are there other symptoms to look out for?
As it gets worse, you'll notice missing, potential pinging, and maybe an anger management light.

Probably make sure you're using only 98 petrol.

Being the internally explodey engines, probably get it compression checked as above.

Sorry dude, sell now or be up for a ridiculous amount of money on a rebuild, and if you're behind on your servicing, even if it is time... Goodwill is even further out of reach, even though it's a known fault.