i found this on here

https://www.thirdgen.org/newdesign/tech/unlimited.shtml

and tried it, and got nothing, no check engine soon light, nothin, and yes i spliced the right wire, no i didnt take it above 115 to find out that it didnt work, i was doing about 35 for a minute and no check engine light, and the speedo didnt drop when i flipped the switch; i got a 91 RS; im wonderin if the wiring diagram is for an older year, does any one got any ideas?????????

 

If you wire it at the ecm your speedo should still work. No signal from the vss will not necessarily throw a code immediatly seeing as no signal is normal for a condition where the rear wheels are not spinning. You can try driving it around longer to see if you can get it to throw a code.

 

thanks