'94 Jetta Fuel Consumption!

[wbalaba]

I have a 2.0 litre Jetta, 1994, auto transmission, at 67,000km in a tropical environment. I don't seem to have any real problem. I find my gas milleage of 20 mpg (about 7km/ litre) to be on a high side. Is this normal? Recently, Jetta could not cold-start until I had the temperature sensor replaced. By the way, does replacing the thermostat with a tropicalized one help fuel economy? Also my airbag light does not go off. I`ve also noted that my digital diplay of time is not clearly readable. Sometimes it`s the milleage display. Please advise.