tach signal

[jakeb]

Does anyone know how the tach signal works? I have a m42 in my 2002 and trying to get the stock 2002 tach to work. I connected it to the signal off the c101 plug but not getting anything. So trying to figure out how I can get it to work or if I should go with an after market gauge.

I was able to really drive the car yesterday and it is fun fun fun. The sound when you stomp on it is pretty insane. I am running two straight trough magnaflows. I will have to take a short video of it.

[christod]

Jake,
Ive got an e21 with an m42 swapped in and Ive run into similar problems.
Heres a post string I started some time ago that should shed some light on the situation.

http://forums.bimmerforums.com/forum/showthread.php?t=946870&highlight=pinouts

Hope it helps!

[christod]

Also, if you want to spend a little money ($80 or so), this seems like the easiest and least finicky solution.

[christod]

http://www.msdignition.com/ignition_27_a_8913.htm