c104

[umana12]

Hi guys. I got an 86es with an m50. The wiring is all hooked and I get spark but no fuel. I've been readin about people wiring their c104 but noone has given a specific answer on where to wire pin 2, which is for fuel. Wanted to see if anyone on here knows to which wire I would be connecting this to. Thanks for the help :)

[lolcantturn]

You can skip all the pins on the C104 and your car will still fire.

[umana12]

On the early models u need pin 2 to start pin 1 and 3 for mpg and rpms

[328ijunkie]

You dont need pin 2 to start.

[lolcantturn]

^this. You don't need the C104 to start. All C104 is, to my understanding, is tach, econometer, and VSS, all nothing related to spark or fuel to start the car. Check your wiring.

[umana12]

http://www.r3vlimited.com/board/showthread.php?t=55261

2nd post

[lolcantturn]

No, that runs in conjunction with the VSS which is not necessary to start.

[328ijunkie]

C104 doesnt have VSS in it at all.

[umana12]

I have read in a few spots that for my year I have to have pin 2 wired..I have checked my wiring and I only get fuel if I bypass the fuel pump relay

[lolcantturn]

C104 doesnt have VSS in it at all.

Think I read something in Beej86's thread about the VSS in the C104. Whatever I've never had an eta so I wouldn't know.

[trackjunkie21]

VSS is not in the C104, you have to wire it from the back of the cluster, this is why alot of times people have problems with soft rev limiters in early model cars, they forget to hook up the VSS.

[Beej '86 325es]

Pin #1 BLK - Engine speed
Pin #2 Not used
Pin #3 YEL/WHT - Fuel rate gauge

Separate from the C104 plug, you need to tap into a signal wire on your speedo for your Vehicle Speed Sensor. I tapped into a BRN/RED wire on the plug on the back of the speedo.

[umana12]

beej wut wire did u need to connect on c101 then for fuel??

[umana12]

if u can check page 1360 in here..

http://www.wedophones.com/Manuals/BMW/1986%20BMW%20325%20Electrical%20Troubleshooting%20Manual.pdf

[Beej '86 325es]

beej wut wire did u need to connect on c101 then for fuel??

Pin 24 on your x20 plug should be a WHT/BLK wire. Connect to that.