Octane issue for 99 Camry 3.0L

I drive a 1999 Camry with a 3.0L V6. When I use 87 octane gasoline, it pings badly, so I use 89 octane. The owners manual does not call for anything but regular unleaded. Can the timing be changed to run 87? If so what is the downside of doing that?



If it’s ‘pinging badly’ on regular, there may be something wrong with the engine or control system. It has a knock sensor that should prevent pinging. With all the computer controls, I don’t think you can change the timing easily.

The engine is probably running rich and / or burning oil. Change spark plugs and air filter, and pcv valve. Check the operation of the egr valve. Use a carbon remover in the engine.