GASOLINE/EXHAUST Issue

Hello Beamers,

I am very new to the BMW world. I currently drive a slightly use 1997 BMW 540i, automatic; it's been 4 months at least. The car is wonderful at times, but of course I've had regulator problems (window) and sometimes the car will stall on me. I am aware that an electrical issue may also be present, but my main concern is the GASOLINE Type. In two days my car guzzled 40 dollars in two days! My little brother suggested I may have an exhaust leak and asked if I was using the correct gasoline. I know this may be a dumb question, but after another friend told me that BMWs use Premium ONLY, I began to worry a lot more, yet the car says 'Unleaded gasoline only'. I then realized (sorry) that Premium IS unleaded.....
Question: Should I have used Premium all this time? If so, what kind of damage have I caused to my lovely BMW?????????

Again, I am very new to this type of import, but I really want to maintain this car for as long as I am able.....

HELP!! Suggestions? Comments? (Be nice)

How many miles did you drive? Traffic, speeds, your driving habits? An exhaust leak ahead of the cats will cause a Check Engine light. Read the stored codes, and report.

My car gets 16-18 in light suburban driving.

Beamer = Name for a Hollywood/SoCal Bimmer. A word at which we cringe.

Oh, LOL I had no ideaa! Will make a note never to use "beamers" again.

Well, I drive apprx. 15 mi. to work....5 of 7 days.

Then at least 10-15 2 of 7 days. I try not to travel too far with it. When I do drive on the highway, in Texas I drive about 80 mph.

So, I would say weekly, I am driving 50 miles. I was told that BMWs are supposed only use Premium gasoline, is this true?

Thank you for responding.

The gas cap will tell you what kind of fuel to use.

You need to get the stored P-codes read, and report back. Go to your local AutoZone.