Old man at the Benz dealership says he’s been driving the same car for a long time and usually only puts in 87 octane in sprinkled with 91 every few times. What problems could this cause? Do I have to put in 91?
Disclaimer: I’ve owned (paid off) the car for 6 years and do put in 91, but trying to cut costs.
Everyone’s right about the minimum octane requirement as stated by the factory to mitigate knocking (bad) or a pull back in timing (resulting in no damage but lower performance).
However, there’s another advantage of using the highest octane fuel, which is cleaning additives. Fuels are pretty much generic, but additives are proprietary. The higher octane fuels generally have more of these proprietary additives, so using them can better ensure cleanliness within your engine.
If you want the additives in all octanes use TOP TIER FUEL.
100% agree. Here’s a link to Top Tier fuels.
You can also run a bottle of injector cleaner through it every few thousand miles and save the prices at the pump