wiring up the rpm gauge

[NigelStu]

this is turning into more of a pain in the ass then i thought, how hard is it to wire up an aftermarket tach?

I should be as easy as tapping into the Black/Blue wire from pin 6 on the ECU/DME.


Someone please correct this if it is wrong, since that is where I plan to pull my RPM signal from (based on the ETM) for the data acquisition system / dash display.

[kman_e30]

ok ive been going about this wrong, my engine is out of an 87 vert, but my harness is out of a 90 vert

[kman_e30]

i figured it out! my harness is the is out of a 90, so the rpm signal runs through the c101 not the c104, so all i did was wire the black wire in the cluster to pin 9 in the c101

[Smelser]

Does the jetronic from the 84 have a output signal for an aftermarket tach?

[kman_e30]

im not sure, this might help you out though

http://wedophones.com/Manuals/BMW/1984%20BMW%20318i%20Electrical%20Troubleshooting%20Manual.pdf