1998 BMW only Premium Gas?

Question

Are we supposed to use only Premium Gas in BMW? its an 1998 one

Answer 1

All the BMWs with OBD-II (US versions 1996 and later) have an automatic OCTANE KNOCK SENSOR which advances or retards the ignition timing in 2 degree increments until the optimum combustion and power are achieved. This timing adjustment is continuously on-going through all engine speeds and loading conditions to achieve maximum power. Yes, you can use regular or mid-grade gasoline, but with a noticeable loss of power because of the retarded spark calculated by the KNOCK SENSOR.

Answer 2

There are too many different BMW's to know for sure. Easy way to tell...check your owners manual. It will tell you what octane rating to use.
Unless the car is a hig performance sports car, such as a Corvette, or a Dodge Viper, you normally do not need high octane fuel. The regular will work just fine.

Answer 3

In a '94 325 your running a m50B25 engine with a compression ratio of 10.5:1, you should use premium, or at least 91 to prevent detentation( or knock). Higher compression motors require higher octane gas, the lower the octane the less stable the gas is.

Answer 4

Philip S is correct. I drive a 97 z3 2.8L and if you use regular unleaded fuel it will slowly decrease the performance of the vehicle (lags in power as you near the red line). It CAN be used, but certainly using premium is much better

Answer 5

Ask a good auto repair man. He might have more recommendations on whether you can also use super or 90 grade fuel. I have a Lincoln towncar 98 and I use the middle one instead of premium.

Answer 6

Your manual will tell you. I know the current cars require it but don't know if the requirement extends that far back. You can also access the information at bmwusa.com. You'll need to input the year and model.

Answer 7

open your door to your gas cap. it will tell you there.

Answer 8

if you can afford the beemer then you can afford the good stuff

Answer 9

no