I am consiste nt ly getting a vss error code one my b20 vtec jrsc 1989 dx civic. mechanical speed cable. (busted at the moment)
1. Will replacing the cable get rid of the code.
2. I unplugged the little blue plug on the back of my instrument cluster.. speedo = no code but will that affect my performance since the ecu is expecting a signal.
Ps. P72 obd1 ecu, hondata s200b, obd 0 car.

 

It should.

 

Doesn't the ECU look at vehicle speed when deciding to activate VTEC? If so, will the ECU still get its VSS signal with the instrument cluster unplugged?

 

The blue plug is for automatic seatbelt light on 90/91 clusters. It doesn't carry the VSS signal.

If you DID unplug the correct wire for the speed pulser -OR- if you don't fix your speedo cable (speed pulser is mounted to the back of the speedo and the speedo cable makes it work) then your ECU sill not get VSS signal.
JPil is right - the VeeTAKs won't kick in and, in generals, a lot of things will be wrong with how your ECU operates.

 

no ****, that why my car been feeling lethargic after i unplugged that plug on from the back of the cluster. (might have been green will double check). it indeed got rid of my check engine light but car got slower. thank u sir