That, to me, sounds like it could possibly be pre-ignition noise.
Pre-ignition can damage your engine.
The usual reason for pre-ignition could be low octane gasoline and/or carbon buildup in the cylinder.
Another reason, but which I think isn't possible, is, that the ignition spark timing is advanced (too much) causing the pinging. The computer should be eliminating this possibility however.
If it were in fact the computer causing this problem, the inexpensive solution would be to install a new knock sensor, which is the usual repair for this. You can Google this.
Pre-ignition can damage your engine.
The usual reason for pre-ignition could be low octane gasoline and/or carbon buildup in the cylinder.
Another reason, but which I think isn't possible, is, that the ignition spark timing is advanced (too much) causing the pinging. The computer should be eliminating this possibility however.
If it were in fact the computer causing this problem, the inexpensive solution would be to install a new knock sensor, which is the usual repair for this. You can Google this.