What happens if u put unleaded fuel in a bmw 325?

i know the 325 uses premium. probably like most bmws use. but what happens if u put unleaded fuel in a bmw 325 or any bmws? will it tear the engine down quicker over time? will it give u worst gas mileage than premium?What happens if u put unleaded fuel in a bmw 325?I think you're talking about regular octane..........?



The answer to your questions are both yes. Just about every new BMW I can think of NEEDS premium gas. If you use anything less than that everyday, it will do bad things to your BMW engine and it will drop gas mileage.What happens if u put unleaded fuel in a bmw 325?
Your car is tuned to run on premium. Running regular 87 once in a while won't hurt anything but using it regularly will make the engine ping and run like crap and use more gas in the long run. Give it the gas you're supposed to give it. If premium is too expensive, get rid of the BMW and get something more practical.What happens if u put unleaded fuel in a bmw 325?umm... premium is "premium unleaded"

regular is "regular unleaded"



but thats stupid so people who want to be specific say "87 octane" "91 octane" "93 octane"





here is the thing... if you have no issues running 87, run 87... if 87 pings run 91.What happens if u put unleaded fuel in a bmw 325?
Yes and Yes.



By not using the required octane, your car can ping and knock and basically lose performance. Yes you "can" lose gas mileage and it "can" cause grief to your engine.



Good luck.What happens if u put unleaded fuel in a bmw 325?And the reason why premium as is needed....



Compression ratio.



BMW engines have relatively higher compression ratio. 10.2 to 12.0 depending on models.