Mass Air Flow Sensor???
- Thread starter CarCrazzy_87
- Start date
If you are talking about the one in your car, it's the easiest to test. Your MAF is a mechanical type. It has a flap that drives a variable resistor, it has three contacts, one for the resistor center and two for the resistor sides. Test with an ohmmeter between the sides and check if there are about 5K (5000) ohms, then check between the center and one side, move the metalic flap and see if the resistance changes evenly without hesitations between the rest and ful throtle flap position.
I sold my 325 six years ago and I'm not sure about the 5K, I'll look for the correct impedance and let you know. Any way, the most important test is the mechanical one I told you.
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I sold my 325 six years ago and I'm not sure about the 5K, I'll look for the correct impedance and let you know. Any way, the most important test is the mechanical one I told you.
Just to help you out while searching - you do NOT have a Jetronic fuel injection system. ALL M20 engines had the Bosch Motronic fuel injection system.
It also might help you to look for how to test the "air flow meter" in your car, since technically, the air flow meter in these cars is NOT an MAF - it is a vane-style AFM (air flow meter).
It also might help you to look for how to test the "air flow meter" in your car, since technically, the air flow meter in these cars is NOT an MAF - it is a vane-style AFM (air flow meter).
http://www.bmwworld.com/engines/m20.htm I believe the Jetronic is the brand name, and motronic is the name of the specific product. I'm confused.
The Jetronic system was on the earlier 318i, and the motronic is an upgraded version of the jetronic.
the 84-85 318i's Jetronic system only controlled the fuel mixture. While the later Motronic system controlled the fuel mixture and teh ignition timing. I forgot were I was reading it, but the info that I read said the Motronic was a Jetronic system with the ability to control the ignition timing. Now the earlier E21 320i used a Jetronic system also.... however it was a "K" system while the 318 used an "L" system. The K system was more mechanical while the L system was completly electronic.
This is my opinion: Bosch designed the Jetronic system first in the mid to late seventies then Bosch and bmw got together and developed the Motronic system. I am pretty sure it was Bosch and BMW together that developed the first motronic system... atleast I could have swore I read it someplace. I found this website that had the innovations of BMW and they talked about it. Now if I could just find the website again.
the 84-85 318i's Jetronic system only controlled the fuel mixture. While the later Motronic system controlled the fuel mixture and teh ignition timing. I forgot were I was reading it, but the info that I read said the Motronic was a Jetronic system with the ability to control the ignition timing. Now the earlier E21 320i used a Jetronic system also.... however it was a "K" system while the 318 used an "L" system. The K system was more mechanical while the L system was completly electronic.
This is my opinion: Bosch designed the Jetronic system first in the mid to late seventies then Bosch and bmw got together and developed the Motronic system. I am pretty sure it was Bosch and BMW together that developed the first motronic system... atleast I could have swore I read it someplace. I found this website that had the innovations of BMW and they talked about it. Now if I could just find the website again.