So a few months ago, I saw the code 30F2 - Glow ignition: cylinder 6 Excessive knock, but it was H30F2, which means a historical code from what I understand, so one that's not active, but was present at some point a while back. I cleared it and it hadn't come back since.
But for the last couple of months, on cold starts only (engine sitting for 5+ hours), the engine would be shaking for the first minute til it warmed up.
I took it in for service, and they figured it's not the fuel injectors, but rather bad plugs and carbon buildup. So they replaced the plugs and did a walnut blast. I'll see how she drives to confirm it's fine.
But I'm wondering, could the code from a few months ago have been related to the carbon buildup, or are they two unrelated things generally?
Haven't been able to find out much on the 30F2 code, other than it's really bad to get one!