Impreza gc8, ej20g.
Long story short, engine makes fast ticking noise when running, follows rpm. I figured it would be hydraulic lifters or timing belt tensioner but seems not. Any ideas?
Longer story: had ringland failure on the previous engine so I figured to go with what I had sitting around. This noisy engine has been sitting (indoors) like 10 years but it was driveable and fine when I left it sitting. Now I needed it, removed oilpan, cleaned it, changed water pump and oil pump, did all the seals, used old intake, old turbo, old exhaust manifold. After I started it, it made such sound, just louder at first. I figured it would be dry lifters. It didnt go away so I changed the lifters for the ones ive had previously on the first engine. I only did the passenger side (rhd car) since it sounded thats where the noise came from. Noise stayed. Then I figured it could be timing belt tensioner(old style with separate pulley), I changed both, noise stayed.
Then I suspected bent valve, did compression test and cyl. 2, 3 and 4 were 8.5bar, cyl 1 9bar. I was also spinning the engine without plugs by hand and by started, no noise.