ok here is what i did i took a tpi motor with a auto trans from a 90 and put it in a 89 with a manual trans. now i am looking to figure out how to get a vss hooked up so i can pass smog. mine is ran off the cable from the speedo but the 90 setup is ran off the tranny and it is electrtic without a cable. if some one could help i would appreciate it.



thanks,
kevin

 

double post

 

You have to run the optical VSS signal from the VSS buffer on your mechanical speedometer (it's a brown wire) to pin BC6 on the ECM. Then you need a PROM change 0x18 b6 to use the optical input instead of the magnetic input the 90 computer normally uses.

Or at least that's what my research indicates (since I have the same situation putting a 92 computer into my 89). I have done the rewiring, but haven't done the PROM end of it yet, so I can't say that this works. I got this from:

http://www.cis.udel.edu/~davis/z28/ECMs/86to92.txt

You could probably contact that guy to find out for sure.

If I get it done first, I'll definitely let you know. If you do it first, then let me know.. hehe.

 

You could put a 90-92 dash in your car... Cost would be about the same.

m-t

 

yes i could do that but then i am faced with the tranny isiue also. all i need to do for now is just a simple fix so i can pass smog out here. ok i can get a prom threw work real cheap now what kind of buffer or optical do i have to do at the cluster? or is there a aftermarcket product that just bolts in or something?

 

You already have the optical VSS and buffer. It's mounted on the speedometer (little yellow box). Look under the dash on the passenger side by the ECM. There should be a clear connector with two black connectors plugged into it (15 pins). Pin K should have a brown wire. That's your VSS signal. Find a way to run that to pin BC6 on the ECM.

 

Ok i figured it out for smog i think! i checked a local shop and they have a vss generater that plugs in where the spedo cable is in the tranny. i ordered the parts and i will get them on wensday ill see if it works.Also i ordered a new prom from work so if it all goes right ill let you know. Or if you know of other ways post it on here so other people with this problem can figure it out!!!!!!