Hi

I have noticed that I have a slight ticking/ tapping sound that increases with the revs and only seems to happen when engine is cold. Is this a common thing on imprezas? I have checked oil and levels are all good so was thinking it may need a thicker oil? Any ideas on what I could check? It seems to be coming from the left hand side of the engine bay near the air box?

 

bottom ends gone............

 

Just a bit of piston slap i expect.

 

+1 most do it. Nothing to worry about

 

Ok thats good to know, it's not easy to hear and when the engine is just ticking over you can't hear a thing. It only seems to be between 2 and 3 k on the rev range that I can hear the noise