Replaced head gasket on 2012 Prius. Engine starts and runs but has a tapping sound. Throwing Code P0016. I’ll be triple checking but I’m pretty sure the timing is right. Could it be the vvt oil control valve making the lifter tick type noise. Or even a bad chain tensioner?
That code is for the crank and camshaft positions not being where the sensors expect to find them for whatever reason setup was done incorrectly You can't correct that with VVTI or phasers that has to be done properly the way the cam phasers work and the VVTI or the oil control valve or whatever. All has to be functioning obviously but if it was all functioning before your engine blew up or blew the head gasket it should be back to functioning when you put it back together so I would be looking at my timing marks set up more than a bad oil valve or what have you Not saying that it can't be that but all that was working when the engine was failing in the head gasket was going south nothing's happened other than the head gasket going south You pulled it off the road in time before anything got bent or seriously broke or whatever so generally that's great everything should go well dirty oil in my generation too will get me this code I literally flush the crankcase and put new oil in it in the code goes away for 9,000 mi something like that and then I do it again this is on an engine with close to 500K on it so I'm not really looking to change a timing chain maybe the complete engine at some point
It happens occasionally the timing is off by a tooth. Various reasons but the proper release of the tensioner is often suspect.