any way to run an electric speedo without the ecm?

[mpascino]

Trying to revive the 91 burb after rebuilding the motor. It's a diesel and I am trying to eliminate the rats nest of a wiring harness. Does anyone know of any way to use the factory electric speedo without using the ecm? I'd rather not convert everything to a mechanical setup..... Any info or wiring diagrams any one may have is appricated. Thanks,
Mike

 

[dyeager535]

If it's a diesel, it doesn't have an ECM, right?

Just trying to figure this out. If it's a 90-91 diesel, the "ECM" is probably ONLY there to run the speedo, and a few other things like cruise, etc. Still entirely mechnical injection right?

 

[mpascino]

There is like 2 million wires comeing out of the ecm. It is mechanical injection. I should technically only need two wires to run the motor. The harness under the hood is an absolute mess. I assume the ecm mainly runs the emissions controls that didn't do much and are no longer there since the turbo install. The truck supposedly has the " antilock " electronic rear brakes that don't do anything either. I suppose those are ran through the ecm as well... I'd go as far as to installing an aftermarket module for the speedo before I reinstall the nest again..

 

[dyeager535]

Thought ABS was under the master cylinder on these trucks? Or is that just a part of it?

Oh well, I'm interested in hearing what all electric stuff the later diesels had on them, I never thought about the 90-91's.