Boxer wrote:kaycy wrote:Is pinging due to lower than recommended RON fuel not bad for the engine?
Yes but the ECU will retard timing well before its audible to the human ear
So yes it'll knock, but only lightly till the ECU adjusts (almost immediatley) and grant you less power
Pinging/knock/det is always bad. There's no such thing as good knock, just the severity varies.
They put minimum fuel requirements on your fuel tank lid for a reason.
There are protective measures programmed into the ECU but they can't ward off all bad situations. If the car is running low RON fuel, high ambient temps, high load (eg: towing, up a hill in a high gear, towing a load or loaded up, high revs, etc), dusty environment (or anything that will reduce oxygen content in the air or the efficiency of the TMIC to do it's job), poor environment or other less than ideal conditions all push the ECU's ability to wind back the engine far enough to protect it.
Think of it this way:
- Correct fuel ~4-5c/l more expensive (maybe $2/tank/fill)
Engine rebuild due to detonation:
- ~$5000 +/-$1000 (more if done by Subaru themselves)
As I always come back to, using oil ~$50 more per fill or petrol 10c/l more is simply preventative maintenance and VERY cheap in comparison to a rebuild.