Speed sensor, no clue whats going on.

[EtaSport]

fuel consumption is from the ecu. It controls the mpg in the dash iirc. The c104 i believe was only 86-87 models under the dash in the glove compartment. They integrated it in the c101 in the engine compartment in 88. You might not even have one. But its a 3 wire connector right next to the ecu.

[equate975]

Yeah I just figured that out, I already tapped the tach signal and now the speed signal off that connector. That must be the last wire I need

[equate975]

Ummm... I just got the speed sensor code again.

Is it supposed to goto the green/red wire?

[Ryan Stewart]

You can run it through the green.red wire and it should work. What I preferred to do was get the plug and pin and add it in the plug that the green/red wire goes into on the cluster. Then it was the white/black or black/white wire from the DME. I dont know the pin #.

[equate975]

I did use the green/red and I also tried the yellow one for kicks. Green/red still gave me the speed sensor code.

I think yellow is the fuel consumtion rate, but that one didnt work on the OBC like it should either.

I did some searching, and found this

http://www.r3vlimited.com/board/showthread.php?t=55261&highlight=c104

"
Pin #1 Black Wire-Engine speed
Pin #2 green wire-OBC Fuel cut function
Pin #3 Yellow/White wire-Fuel rate
"

I hope black is not the speed wire, I have that hooked up to my tach, thats what THR said to do.

[Ryan Stewart]

Ohhh, from the 2 pin thing?

none of those are vehicle speed. The black wire is engine speed (aka tach). You have to run a whole new wire from the plug on the back of the cluster itself to the engine controller. There is no vehicle speed signal for the DME on motronic cars.

That is why its so rediculous when people say, "I am certain I have a speed limiter."

[equate975]

Ohhh, from the 2 pin thing?

none of those are vehicle speed. The black wire is engine speed (aka tach). You have to run a whole new wire from the plug on the back of the cluster itself to the engine controller. There is no vehicle speed signal for the DME on motronic cars.

That is why its so rediculous when people say, "I am certain I have a speed limiter."

Ahhh ok. Right now I do have that green plug on the cluster with one waire connected to it. I hve been looking at the ETK and I cant figure out what wire it has to be, would that be the one?

Thanks again

[Ryan Stewart]

The wire currently going into the green plug is the signal for the cruise control. Just get another plug and plug it into one of the other 2 and you will be fine.

Its an issue neglected on EVERY online document.

[equate975]

The wire currently going into the green plug is the signal for the cruise control. Just get another plug and plug it into one of the other 2 and you will be fine.

Its an issue neglected on EVERY online document.

Can i just tap into the existing wire? Because I did. I couldnt find a plug that would fit in there.

I dont have cruise anymore anyways, if it would make a difference.

[devinwwu]

curious if you got this figured out as i have the same problem. cuts out anytime i put my foot down past 3/4 throttle. I'm assuming the same reason cause i pull the same code...

let me know if you fixed it

[EtaSport]

If you check your diagrams for your ecu pins you'll see a speed signal wire. Run a wire from the green cruise control plug on the instrument cluster and it will go away. It did on my car.

[devinwwu]

did your fuel cut symptoms go away too?

[EtaSport]

I seemed to have a problem with high rpm reving before even though I rarely got it that high. Afterwards it never flinched. Code was gone.

[PiercedE30]

Anyone have an example diagram?
Not like an exact replica of yours but, errr, I dunno how to say it.

[Jason89i]

re: road speed signal......

http://www.r3vlimited.com/board/showthread.php?t=75194&page=3&highlight=road+speed+signal

post #39 and #42.

cheers, jason