Hi, I'm having a weird problem on a Honda CRV 07 after I replaced the head due to overheating.
The car had been overheating several times, still don't know the reason, and the head had become uneven because of the heat. So I left the head to a guy who grinded, made it flat, then I reinstalled it again with new gaskets etc.
First startup was rough and tricky, it smoked a lot, guess it was old coolant getting burned in the exhaust, after that the idle and starting was rough. I replaced the ignition coils and spark plugs. Fired it up and got it up to temperature, took a shorter test drive. I cleaned the throttle body and inlet manifold, checked the injectors wich seemed fine. Turned it off and started again and starting was a bit better than before. The Idle wasn't that bad either now. At this point I felt like it ran good enough for me to feel happy.
Took it for a longer test drive to see how it felt in higher revs and speed, were it felt great. But when I came back the idle was a bit low and rough.
Next day when I tried to fire it up, I didn't want to start. I could see and smell how it got fuel but it sounded like it didn't fire properly. Later that day after recharging battery I did another try and after letting the starter work for a while it slowly fired up. Still with that rough and low Idle.

Any ideas of what causes this starting and idle problem can be? For me it feels like something is wrong with the ignition.

The car has a R20A engine with automatic gearbox.