Please help me diagnose this

Lately my car been having rough starts the first minute and then it runs great after that (mileage is still good). Engine throw a code which I looked up to be cyl 2 misfiring . Coolant is a quart low. I assumed it's the head gasket leaking coolant slowly into cyl 2 which cause the shaky start. This car has 266k miles and I was planning to replace it in 2 years so I put in head gasket leak repair hoping to bandaid it for another 2 years. Problem seems to go away for 2 weeks or so and now I got engine light and really rough start.

I think this is important but after the rough start, if I turn off the engine and turn it back on there is no noise, so this is only for cold start!

I will upload a vid file when I get home, thanks for the help!

 

Hi guys, its not technically a snake oil, a lot of people have success with it as a temporary solution for low head gasket leak. It supposed to fill up the leak and turned into solid as it cooled down. (the cap on my bottle broke during shipment and the liquid filled the crack on the cap and turned solid, it's pretty cool to see!). It does not work in all cases, just very minor head gasket leak.

Here is a video i made of the noise during cold start up.

 

After the noise dies down, I had no problem driving home. Acceleration was smooth with no loss of power.

 

No, the problem is still there. I'm just stating that after rough engine start, it drives just fine. But the problem will still be there the next time I cold start the engine

 

yes, oil is clear, no signs of coolant.