Why You Should Clean Your Fuel System For Better MPG

The light turns green, you press the accelerator and your vehicle lurches forward, but with less oomph than you’re used to.

Later, when stopped at a red light, you notice the engine idling roughly.

There’s no warning light on your dashboard, but your engine may benefit from a thorough fuel cleaning service.

“An engine knock or a minor rattle may get drowned out by music or traffic noise,” said Tony Molla, vice president of the Texas-based Automotive Service Association. “Those little nuisances can turn into expensive repair bills if left unattended.”

Over time your injectors, intake valves and cylinder heads get dirty. Carbon created by the combustion process accumulates over time and prevents your engine from running efficiently.

The result: lower miles per gallon.

Experts recommend cleaning your fuel system from time to time. Some suggest performing a fuel system cleaning when you replace the engine’s air filter, or while performing a tune-up.

A typical fuel system cleaning begins with inspection of the system for leaks and damage.

A special cleaning additive is put into your gas tank, followed by a second chemical that courses through your engine via a vacuum line connected to your fuel line. Together, these sophisticated chemicals remove sludge, dirt, grease and deposits from your fuel system.

Your vehicle’s fuel filter captures contaminants like rust, dirt and debris.

A clogged filter reduces the engine’s ability to receive the proper amount of gasoline to function. If the fuel filter is completely clogged, the engine will not run at all.

Have the fuel filter inspected frequently if you drive in dusty or smoggy areas.

Ask your service advisor if replacing the fuel filter is part of the fuel system cleaning. Replacing the fuel filter might be considered a service separate from a fuel system cleaning.

Molla offers the following insights about fuel system maintenance:

  • Carbon build-up occurs naturally. Although small amounts of deposits are no cause for concern, excessive build-up may damage the engine or catalytic converter and sensors.
  • Know the tell-tale signs. That includes reduced fuel economy, rough idling, slower-than-normal acceleration or increased emissions.
  • Use the recommended fuel. Lower octane fuel in a high-performance engine increases problems with carbon build-up.
  • Follow the manufacturer’s recommended service interval. Most vehicles require a fuel system service somewhere between 60,000 and 100,000 miles. Consult your owner’s manual to see what your manufacturer recommends.
  • Fuel quality matters. All gasoline contains detergents that prevent carbon deposits, but how much detergent varies greatly. Premium brands use more detergent, bargain brands less.
  • Fuel injection cleaning might not be necessary. Check with your trusted service advisor and your service interval schedule.