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Fleet

Common Maintenance Problems That Contribute to Poor Fuel Efficiency

June 29, 2015

The American Council for an Energy-Efficient Economy reports that the transportation industry is responsible for nearly 30 percent of the nation’s energy consumption annually. Unfortunately, much of this fuel goes to waste as the result of unchecked maintenance problems in cars and trucks. This fuel waste translates to greater costs for companies with vehicle fleets and tighter budgets for fleet managers. Thankfully, these wasted resources can be recouped by implementing more rigorous maintenance schedules. Several seemingly insignificant repairs can make a huge impact on fuel efficiency.

Misfiring spark plugs
Working spark plugs are a critical component for fuel efficiency. In fact, the National Institute for Automotive Service Excellence notes that bad spark plugs can cut a vehicle’s fuel efficiency by up to 30 percent. Spark plugs are responsible for igniting the mixture of air and fuel that powers the pistons in a car’s engine. Pistons are designed to set off in rhythm to minimize vibrations and wear. A spark plug that misfires offsets this rhythm, causing pistons to misfire and increasing the total workload for the engine.

Warn drivers to keep an eye out for sudden, noticeable drop in fuel efficiency. Misfiring spark plugs compromise an engine’s performance immediately, and drivers will save money and fuel by getting the spark plug replaced immediately.

Under-inflated tires
Most drivers and fleet managers know that tire pressure is important for fuel efficiency, but the impact of under-inflated tires is so significant that this advice warrants repeating. The Department of Energy notes that 1.25 billion gallons of fuel are wasted each year due to tire pressure problems alone. Furthermore, under-inflated tires wear significantly faster. Tire pressure is not just a matter of reducing fuel costs. Fleet managers can cut spending on new tires by impressing the importance of tire efficiency on drivers.

Dirty filters
A new air filter can improve fuel efficiency by up to 10 percent, according to DailyFinance. Air filters prevent debris and dirt from reaching critical engine components and building up as deposits. Excessive debris will eventually interfere with the performance of the engine and so will reduced airflow from a clogged filter. Fleet vehicles can be spared these efficiency problems if air filters are replaced on a routine basis. In this way, regular filter replacements also contribute to the long-term performance of the engine.

Bad alignment
Investopedia reports that misaligned wheels cause fuel efficiency reductions by up to 10 percent. The causes of this drop in performance are similar to problems caused by under-inflated tires. Poor alignment prevents tires from rolling flush against the surface of the road. Increased friction causes tires to wear more quickly and places a greater demand on the engine to keep the wheels rolling. Driving a vehicle with a crooked alignment will also put extra strain on bushings, joints and other vehicle parts that depend on a properly aligned frame.

Dead oxygen sensor
Oxygen sensors make it possible for a car to combine the right mixture of oxygen and gasoline inside the engine. The sensor scans the content of vehicle emissions and uses this information to determine if the engine needs more or less oxygen to reach the ideal ratio. If the oxygen sensor fails or malfunctions, the engine is forced to run on pre-programmed ratios of air and fuel. These settings are far less efficient than those set by a working sensor. A malfunctioning oxygen sensor could also interfere with the performance of engine pistons. Inconsistent mixtures of oxygen and gasoline could cause pistons to fire off-time and greatly hamper the performance of the entire engine.

Keep these maintenance issues in mind when scheduling repairs for your fleet. A bit of preventative care will go a long way toward cutting your costs.

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