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Now that you have a broad knowledge of how an airflow meter works you are ready to test the MAF sensor. If the problem is at the circuit level changing the sensor will not solve the problem.
A MAF sensor that behaves like this will require replacement.
Mass air flow sensor troubleshooting. Troubleshooting a Mass Airflow Sensor. Now that you have a broad knowledge of how an airflow meter works you are ready to test the MAF sensor. First open the hood of your vehicle and locate the MAF sensor on the air cleaner assembly.
Usually youll find it between the air filter housing and throttle body. 3 Symptoms of a Bad Mass Air Flow Sensor 1. A bad MAF sensor can cause your vehicle to experience poor drivability issues such as engine stalling jerking or.
Your vehicle needs the proper ratio of fuel to air in each combustion cylinder. Running rich means there is too much. Troubleshooting mass air flow MAF sensor problems can become a major headache for import technicians because the failure is usually one that involves a calibration error rather than an outright electrical or mechanical failure.
Because calibration errors tend to be. Symptoms of A Bad Mass Air Flow Sensor 1. Check Engine Light appearing on the dashboard.
A bad mass air flow sensor will usually trigger a check engine light. An engine that is difficult to start. Since the ECU cant measure incoming air mass it needs to compensate for this.
Here are some of the most common symptoms of a faulty mass airflow sensor. The engine is very hard to start or turn over The engine stalls shortly after starting The engine hesitates or drags while under load or idle Hesitation and jerking during acceleration The engine hiccups Excessively rich or. If the engine control system is working correctly you will probably never notice this except for a change in fuel economy.
A trained technician will have to look at fuel trim status with the use of a scan tool to verify this. A MAF sensor that behaves like this will require replacement. Before changing the sensor a complete diagnosis of the entire circuit is indicated to check its correct functioning.
If the problem is at the circuit level changing the sensor will not solve the problem. A MAF sensor that has failed irretrievably will not transmit air-related information to the PCM. How to Repair a Mass Air Flow Sensor Step 1.
Open the hood of your vehicle and locate the mass air flow sensor on or near the larger air cleaner box. Remove the the two screws that hold the mass air flow sensor to the intake system. Pull the mass air flow sensor out of the intake.
The most reliable early symptom of a failing or failed MAF is the illumination of the check engine light on the instrument panel. Many types of problems may cause this light to come on so you must have your cars computer analyzed to see if the light is related to the mass airflow sensor. Locate a mass airflow sensor in the engine bay.
Nissan MAF sensor is located right next to the engine air filter housing typically on the drivers side. Unplug the electrical connector from your Nissan mass airflow sensor. Watch the following video on how to remove the air filter box to access the MAF sensor.
Auto repair shops hate this video. If your check engine light is on you could have a bad mass air flow sensor. MAKE SURE YOUR MASS AIR FLOW SENSOR IS CLEAN.
Cleaning the Mass Airflow Sensor. Often the mass airflow sensor really only needs cleaning when they go bad. Some folks recommend using alcohol because its usually on hand and can clean the sensor.
This is a bad idea it can ruin the sensor. Uses mass airflow sensor cleaner. Its really cheap and available at any parts store.
It sure beats the heck out of having to buy a new sensor. If the sensor is connected properly both electrically and to the intake manifold use a scan tool or voltage meter and vacuum gun to check MAP sensor output. Youll have to look up a chart to measure voltage against no vacuum and full vacuum.
A bad MAF sensor is fairly easy to detect from the very beginning. You just need to be able to recognize the symptoms as they occur so that you will know to associate them with a possibly faulty mass air flow sensor. Locate the mass airflow sensor near the engine air filter housing.
Press the red clip slightly to unlock it. Unplug the electrical connector from the mass airflow sensor. Remove the screws that hold the mass airflow sensor in place.
This is one of the problems caused by bad mass air flow sensors. So when you see this symptom try to replace the sensor. Turning over is difficult.
When the mass air flow sensor is faulty it can be hard to turn over the engine. In fact you may even find it hard to start the engine. In modern cars the only way to test the mass air flow sensor is with a scan tool.
Mechanics measure the amount of air flow mass air flow sensor readings at different RPMs. They compare the readings to the specifications or to the readings of a known-good mass airflow sensor. The most obvious one is that the check engine light CEL will be on on your instrument cluster and driving you nuts.
Here are a couple of others. A MAF sensor diagnostic trouble code DTC stored in your vehicle computers memory. Lean andor Rich diagnostic trouble code s.
Fuel Trim diagnostic trouble code s.