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.
Throwaway’s statement is actually true: Even with knock sensors and ignition retard, you can still have detonation and engine damage. There’s a limit to how much the computer can retard spark
It can cause engine damage in certain extreme circumstances. The statement made was that it does cause engine damage which, in the context it was used, implies (a least to me) that you can’t even run 87 one time. Unless your car has an aftermarket tune, it’s likely not to have an issue.