Originally Posted By: tacoguy714
pinging cant be good for any engine, so my question is mid grade or premium worth the added cost vs effects on engine. I'm trying for the million mile club :}
Very light engine pinging is ok for an engine. Some engines are designed to do so to optimize efficiency. Heavy constant pinging or knocking is not. The ECM on a modern engine will detect the latter, and retard timing accordingly. But mileage and combustion temps will suffer.
Use the recommended octane. The % cost difference is often less than the % mileage loss of using lower octane; miles per $, the higher octane, if required, is the better value.
If you have excessive pinging on recommended octane, try a combustion chamber cleaner (Techron), or change gas stations. On some engines, resetting the ECM to clear drive data can provide a fresh start.
FWIW, gas loses about 1 octane point/month. The fresher the fuel, the better.