When budgeting for travel this summer, be sure to take fuel mileage into consideration. Neglecting the condition of critical systems and components can cut your gas mileage in half. Most of these services represent little or no investment; some cost nothing such as tightening the gas cap or keeping tires properly inflated. Others are obscure components in the engine management system that affects performance and economy.
The oxygen sensor is a good example. It is a part of the emissions control system that monitors exhaust, adjusting computerized engine controls to compensate for discrepancies in fuel and ignition systems. When neglect exceeds the limits of adjustment, performance and fuel economy deteriorate. Many vehicles are not passing emissions testing due to this part failure.
Another example, the computerized controls that adjust for a dirty air filter, can only adjust so far. When the condition has progressed to the point where no further correction can be made, performance and fuel economy go down hill.
Based on average fuel economy of 20 miles per gallon (mpg), neglected maintenance could cost you dearly in the following areas.
• Under-inflated tires increase rolling resistance costs .6mpg
• A dirty air filter causes excessively rich fuel/air mixture costs 2 mpg
• Worn spark plugs causing inefficient combustion and wasted fuel costs 2mpg
• A worn oxygen sensor unable to compensate for engine malfunctions costs 3mpg
• Dirty or substandard engine oil causes engine friction costs .4mpg
• A loose gas cap allowing fuel to evaporate costs 2mpg
If all these common items were neglected you would have a potential loss of 10 miles per gallon. With gas prices as high as they are these days, you should really sit up and take notice. Especially if you have a truck like many that is rated at 14-16 miles per gallon. It's only money, right?
