Hard Start After Sitting (1 Viewer)

[motormayhem]

This past week my LC has hard started twice. After it’s sat for a few days it will crank a bit longer and when it starts it stumbles like it is misfiring and makes a pretty loud knocking sound like there is a major mechanical issue. Then it clears up and is happy. Was a bit worried it could be a head gasket leaking. Coolant looks fine/no bubbles, oil looks good, doesn’t smoke excessively (always a little condensate as it warms up but normal for a gas lol one engine). I also did a combustion leak test from autozone and it passed.
What else should I check? Starts fine after that so it has to sit for ~2 days to make this happen.
Just got back from a 1000 mile trip recentlyand it was happy on that.

 

[rolliges]

Starter??

 

[motormayhem]

Starter??

I’m pretty sure the starter is fine. The issue starts once it’s running (missing and knocking). Cranking is smooth and normal speed.

 

[rolliges]

That's beyond me. There are 2 (i think) knock sensors. Perhaps they could contribute. Others will be of more help.

Missing could be a fuel vs. air problem (if it's not something worse) or timing. But I'm just guessing....