Yeah its not just an engine knock, i've heard people saying all different things it could be, like spun cam bearings or spun rod bearings, broken valve, slipped piston ring...everything man, maybe i should rip another CA20e out of a pinny or corsair, yeah i dunno ay, its just a really loud engine knock, sounds as if its coming from the block because you can hear it really loud inside the car and you can hear it down the street lol. and when u crank the starter motor its sounds as if it cranks really slow like the battery is exhausted (but its not...) yeah its pretty frustrating since i have rego coming up this week ay.