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.
Really nothing. I have an old VW tuned for 93 on the ECU but I can still run 91 and 89 the ECU will compensate for it and I’ll lose a bit of performance to prevent knock.