What does the MAF sensor on a VW Jetta do?
A MAF sensor measures the density of the air entering the intake manifold. It passes this information onto your Jetta’s ECU. The ECU uses this information along with other sensor data to control the amount of fuel that enters the combustion chamber. If you do determine that you need a new mass airflow sensor, they aren’t too expensive.
Why does my VW not set a MAF code?
The car will not idle or idle rough. Black smoke coming from the tail-pipe. A tremendous lack of power upon acceleration. In other words, you can start the car, but when you press the accelerator pedal, the car just won’t move. A MAF sensor code. But not always. I have replaced fried MAF sensors on different VW’s that never set a MAF code.
What happens when the MAF sensor goes bad?
The test in this article is for the Bosch MAF sensor that produces an analog voltage signal that can be measured by setting the Voltmeter in Volts DC mode. Your VW car can display any number of different symptoms when the Air Flow Meter (MAF sensor) goes bad but, the most common ones are: The car will not idle or idle rough.
How to test mass air flow ( MAF ) sensor?
Just eyeball and physically shake/move the ducting to see if it’s loose or disconnected. OK, you’re gonna’ start by checking the basics. These are 12 Volts and Battery ground to the MAF sensor. After that, we’ll test the actual performance of the MAF sensor as the engine is running.
How to test the 5 wire mass air flow sensor?
The most common way to test the 5 wire VW Mass Air Flow (MAF) sensor is just to unplug it with the engine running. If the MAF is bad (either because it’s not producing a signal or producing an erratic one), the car’s idle will return to normal and the car will seem to run fine.
What kind of air flow sensor does a VW use?
Before I go on, let me tell you that VW uses several types of mass air flow sensors (also known as Air Flow Meters), for the most part they can be divided into two categories. One type has a connector with 4 slots for only 4 male spade terminals and the other has 5 slots for 5 or 4 male spade terminals.
What are the plugs for the mass air flow sensor?
4B0-973-724 is the connection for the Mass Air Flow Sensor, coils, and the like, and runs around $30 each from the local dealership. 4B0-973-712 is the smaller plug used for the Temperature sensor, AIT sensor, Throttle Body and like connections.
How to check the wiring of a VW Jetta?
Using the test box V.A.G 1598/18 the wiring can be checked according to the wiring diagram. NOTE: – Before connecting test leads the correct measuring range on the tester must be adjusted. Otherwise the electronic components can be destroyed! – Use the multimeter V.A.G 1526 with auxiliary cables from V.A.G 1594 for testing.
How much does a mass air flow plug cost?
4B0-973-724 is the connection for the Mass Air Flow Sensor, coils, and the like, and runs around $30 each from the local dealership. 4B0-973-712 is the smaller plug used for the Temperature sensor, AIT sensor, Throttle Body and like connections. That part will run about $12 at the dealership.