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.
My car isn’t modified but the manual says it will cause engine failure and override any form of factory warranty if 91+ isn’t used. Is this a hoax?