On the inside area of the gas door is states 91 octane recommended. I've only put 93 in since purchasing my X3 last April. Has anyone put 89 octane in and sort of danger in doing so? Thanks, Scott, Holland, MI
It's best to use what's recommended for optimal running, efficiency, & power, since that's what the engine tuning is based on. The control systems would do their best to compensate, but at best the compensating equates to less power & efficiency; at worst, you get knocking/pinging that doesn't get compensated for and end up suffering engine damage. https://www.carsdirect.com/car-repair/3-causes-of-engine-knock