Hello all. I need advice please! My '89 740GL (235k mi) is getting increasingly horrible fuel economy. Normally, I would get anywhere between 300-330 miles to the tank with mixed highway/city driving. Over the past few months I have been only able to get maybe 200 miles and this past week I got only 170 miles to the tank! I fill up when the needle is in the red zone. I believe the fuel gauge is working because when I fill I usually get 12 or more gallons. What I don't understand is that there have been no performance symptoms or obd codes with exception of sometimes slight hesitation when I accelerate from a stop. Where do I start!? I need the car to last at least 2 or 3 more months so I can't go on like this. If someone could point me in the right direction I would be appreciative. Thanks everyone!

--Steve G. ('89 740GL Sedan 235,000 mi and counting)