What is the capacity of fuel tank in a 1998 Mercedes Benz 230?

The fuel tank capacity for a 1998 Mercedes-Benz C230 (assuming you mean the C-Class, as there wasn't a separate 230 model that year) is typically around 16.4 gallons (62 liters). However, there might be slight variations depending on the specific model and trim level. It's always best to check your owner's manual for the exact figure.