Can bad spark plug wires cause overheating?
Incorrect ignition timing is most extreme cases of a poorly running engine that can create extra heat but even things like worn spark plugs, a clogged fuel system or a dirty airflow sensor can cause your engine to create extra heat and run hot.
Can you have too hot of a spark plug?
The most serious result of selecting a heat range that is too hot is overheating. Overheating will cause the electrodes to wear quickly and can lead to pre-ignition. … When the spark plug firing end (tip) temperature exceeds 800°C, pre-ignition originating from the overheated insulator ceramic can occur.