But I assume once its up to 60+ degrees C, it goes away?

THen, as I am facing same dilemna, prechambers. Actually I think I have one bad is all. Biodiesel is helping somehow.

BTW, when you cracked the injectors, did the stumble/lope mitigate at all on any particular injector?

Lastly, I dont have adjustible valves, but many of these do. It would be the next thing I'd eliminate as a variable.

Please reply with exactly which year/engine you;re working on.