The mass airflow sensor (MAF) in your Nissan vehicle measures the amount of air going into the engine. If the MAF sensor sends the wrong signal to your car's computer--because of dirt or other contamination around its sensing elements--your engine will be fed with the wrong amount of air/fuel mixture. Follow some simple steps for cleaning to restore your MAF sensor's operation and engine performance to normal.
Park your Nissan vehicle in a safe place, with enough room for you to work around the front of the car. Open the bonnet.
Locate the MAF sensor electrical connector. The sensor is mounted in the fresh air intake duct--close to the throttle body, fuel-injection system or air-filter housing, depending on your Nissan model.
Remove the MAF sensor mounting screws with a Phillips-head screwdriver. Set the screws in a safe place; then remove the air-cleaner duct or air-intake assembly to reach the sensor inside the system. Depending on the model of your vehicle, you might need to remove one or more clamps using a standard or Phillips-head screwdriver, or disengage wire clips to take the air-intake assembly apart.
Dismount the sensor from the air-intake assembly, being careful not to damage the sensor's electronic sensing elements.
Spray the MAF sensor wires or grid (sensing elements) with electrical component cleaner or MAF sensor cleaner. (See Tips for more information.) Rub dirt and contaminants off the sensor elements using a soft brush, until the wires and sensor components are completely clean.
Mount the cleaned MAF sensor in the air-intake assembly. Install the air-intake assembly, plug in the sensor electrical connector and install the sensor mounting screws.
Consult your owner's manual or vehicle service manual to identify or locate components. You can buy one at most auto parts stores, or consult one for free at most public libraries. You can buy electrical component cleaner at any electronic-parts store; most auto-parts stores carry mass airflow sensor cleaner as well.
When unplugging the MAF sensor from its electrical circuit, make sure the ignition key is in the "Off" position. If you leave the ignition on while unplugging the sensor, your car computer will store a trouble code and the "Engine" light might come on. It could take the computer over 40 engine-starting cycles to clean this trouble code.