After a couple of days without use I started the car this morning to be greeted with what sounded like the dreaded piston slap if the throttle was opened gently, although I suspect it could possibly be the cam belt tensioner bouncing against its stop.
It goes to prove that no matter how well you treat the car with gentle warm-ups, best oil etc it still comes back to bite you!
Anyone else with an 03 STi (15k miles) showing these signs on cold mornings?

JohnD

 

Pound to a penny it's the cam belt tensioner mate. Get it checked out for piece of mind, but I'd be VERY surprised if it was piston slap. Cars make more noises in the cold until they warm up. The first winter with my MY99 every time I started it up I was convinced I could hear piston slap or the bottom end giving up! When you like a car as much as most people like their scoobies, you just tend to get a bit paranoid.

NS04