Fireman, This link might help you
Engine Tune and Performance
But before reading the page do the following things, because as per your given symptom "Warmer days" is quit a good suspect to diagnose.
1. Check your PVC if your car is non turbo, even clean few months before oil gases can go back to T type hose from where it goes to your ETM Air hose, therefore it might be a time to clean ETM Again, along PCV Oil trap check.
2. You have not mentioned either it stopped the engine or just does not response while engine is still running, have close look on the electric cables.
3. I am kind a sure it mostly happens when you use the AC ON. Try turning it off.
Send the video if possible, when there is no code might, there might be a small problem to fix.