How to Clean the MAF on a Lexus

Many car owners are aware that replacing your air, oil and fuel filters on a regular basis will help keep your car running smoothly and maintain fuel efficiency. Fewer people are aware of the mass air flow, or MAF, sensor and the part it plays in your car's fuel economy. This sensor detects the amount of air in the engines intake system and, in conjunction with the electronic control unit, controls the amount of fuel supplied to the engine. A dirty MAF can lead to excess amounts of fuel being used, rough idling, sluggish acceleration and reduced power. Cleaning the mass air flow sensor every two years or 20,000 miles will help prevent this problem.

Things You'll Need

  • Philips screwdriver
  • Cotton swabs
  • Isopropyl alcohol, 99% pure
  • Oil
  • Remove the electrical connector from the MAF. The sensor is located on the exit port of the air intake box, which houses the air filter. Depending on the model of Lexus it may be easier to remove the lid from the air intake box to access the mounting screws holding the MAF.

  • Remove the two screws from the MAF housing and pull out the sensor.

  • Looking into the tube of the sensor you will see two wires. Spray the wires with the alcohol and shake the excess out of the sensor to dry it. Spray some alcohol on a cotton swab and use the swab to clean the wires more thoroughly. Wipe gently to prevent damaging the wires. Once cleaned properly both wires should be silver in color. Shake the sensor dry again.

  • Spread some oil on the o-ring of the sensor and replace it in the housing. Install the mounting screws, replace the air intake box lid if necessary and reconnect the wiring harness to the sensor.