Vehicle speed sensor (VSS).

I transplanted a TPI 5.7L motor and 700R4 transmission from my old 1987 GTA into an early none TPI “F” body Car (clean body no rust). I used a “Painless Wiring Harness”. I did not connect the VSS, I by-passed it because I am not using a lock-up torque converter, or emissions devices; EGR, air pump etc (not needed in that year of “F” Body car in my area)

The car seems to run fine without it. Can anyone please tell me if it will hurt anything to run my motor without this? Does the VSS do anything other than control the lock-up converter and emissions devices? I need to make sure before I have my transmission modified so I can us the mechanical Speedo cable.

 

It is used for IAC control based on road speed to allow a smooth coast down to a stop, if it is a SD system it will stay in fuel trim cell 4 unless you change the parameters in the PROM, DecelFuelCutOff will not be functional, highway fuel mode won't work eventhough I believe GM kept it disabled. There are a few companies that make senders for cable drive speedometers. It isn't really needed to run one but it can help the driveability of the vehicle.