Hi I have a Legacy B4 which has a problem with the MAP and I recently ordered a new one but unfortunately the sent me a wrong one but they said a 5pin airflow sensor can work if connected to the 4pin adapter, can someone help me with how this can work? When i connected the 5pin air flow it sure worked but the vehicle couldn't manage to stay at idle, its cutting even at traffic lights???? Attached are photos of they are different.

 

 

 

Help me.. 

Well in the picture that's a MAF sensor. (mass airflow)

MAP (manifold absolute pressure) is a different sensor.

 

How do you know there is a problem with the sensor? Check engine light is on? If so post the code number.

 

I'm not sure of the difference between the 4 pin and 5 pin MAF sensors on these. You would be best to exchange/return it for the proper sensor.

They both look the same to me, except one pin is missing on the MAF in your car.  So, have you looked in the connector to see if the missing pin broke off and is stuck in the socket?  This could be why your MAF isn't working in the first place.

 

It is also possible that the pin got bent over and broken and fell out onto the ground somewhere, but if you have five clean sockets, I'd say plug it in and see if it works.

 

Little tip here, disconnect the battery for a few minutes before restarting the car.  This is a case where the computer really needs to relearn the fuel trim as the new MAF probably won't be an exact match for the resistance profile of the old MAF.  It's faster if the CPU doesn't have to figure out that the old profile is bad before it starts learning the new one.