Thanks,Be sure the car has oem sensors and parts other than the plugs. Plugs need to be oem from the 2016+ VT.
3k mile oil and filter changes max with proper full synthetic oil. What you have been using is the wrong weight for sure and not sure of the specific oil used.
Do check all wiring and connections including all the grounds in and around the engine bay.
Let me check which plugs I put in last. Used 91568 NGK.
Oil changes and filter done as per, (it's 5000km which is around 3000 miles). Oil used is per manual and many done at the dealer. As per them, and what I buy if doing it elsewhere is Quaker State Full Synthethic 5W30.
I will do my best to try and check all the wiring.
I put in some Techtron fuel system cleaner today, and low and behold it CEL actually went out....... But it could of been a pure coincidence as it only went out for about 60km and then came back on again.
Still no change in performance or any strong indicators there is actually an issue (unlike when the crankshaft started to go bad). As well as when the coil pack(s) started to go, both CEL and misfire. After swap CEL never came back and no more stuttering / rough idles.
This one is kind of weird, because initially after swapping the O2 to a OEM bank 1 sensor 1 position. The CEL stayed off when cleared for 2-3 weeks completely. And before the swap was constantly on. But now it seems like it just comes one for a few hundred KM, then goes off for a bit, then comes back on again with nothing I can tell or pinpoint exact when or why. Other then the fact that it seems to mostly pop back on if idling (like I run into the store just to grab something quickly) I come out and it's one.