Hi, my B16 is acting up on cold starts. The tach shoots up to about 3000rpm right after it cranks, but idles up fine at about 1500-1000 rpm about a couple of seconds after. I've watched some videos that show cold starts and it cranks smoothly and shoots up to 1500rpm max, then idles right after. I know it isn't anything major but it puts unnecsssary strain at the bottom end as the oil pump needs a couple of seconds to build minimal oil pressure and it's not exactly a new engine at 136k miles. I'll check the main bearings on the next oil change as I've also noticed a louder mechanical noise that lasts for a second when it starts up. FITV is deleted using a gasket and the coolant line has been rerouted, IACV has been already cleaned and inspected. Oil pressure is fine, about 4-4.5 bar (58-65 psi) on cold starts with a 1000-1500rpm idle. I really don't know what else to check, already checked for vacuum leaks and couldn't find any.