how to test a A.F.M in situ

[arrisbmw]

Hi Can Anyone advise me how to check my air flow meter is working o.k. on a 89 m40 engine . the plugs looked a bit black and not getting good mpg, so wondered if mixture is too rich, and is this component working correctly.
thanks in advanced.

[arrisbmw]

anyone ? .. thanks,
when i checked my flap its moving in and out with little resistance.

I double check my mpg. may be not as bad as i first thought 7.5 miles per ltr.
anyone got their mpg ? or miles per ltr please .

[BenHar]

http://www.e30zone.net/modules.php?name ... t=afm+test

Ben

[arrisbmw]

cheer Benher. good post.

[Brianmoooore]

7.5 miles/litre = 34 MPG, which isn't bad for an E30 in mixed driving.

[arrisbmw]

yes . i,m figuring now everything is o.k. after my tlc, new battery was the last consumable fitted.
but i,m still keen to learn amap about the car. (as much as possible). I like to know how everything works and fits together in the little beauty.

in the post about checking the afm. can that be done without taking the black square top off, if so are the terminal numbered , so you know where to connect the battery small 9v, and where to test voltage curve. mines under a round connector,
guessing i got 5 terminal
2 x for temp = resistance test ,

1 x for 12v live supply and 1 x ground .

1 x 5volt signal wire is that right ? thanks

[Brianmoooore]

Battery negative to pin 5, positive to pin 1, meter negative also to pin 5 and meter positive to pin 2.

Pins 4 and 5 are for the intake air temp. sensor, and pin 3 is the output from the CO adjustment pot.

[arrisbmw]

thanks very much. helpful as always. cheers Paul