I HAVE A 96 CIVIC HX, I DID A 2000 SI SWAP. HARNESS, LINKAGE, AXLES...WHAT I DID WAS TAKE OUT THE OLD ENGINE N HARNESS AND PUT IN THE NEW ENGINE W/ SI HARNESS. IM CONFUSED BECAUSE MY CHECK ENGINE LIGHT COMES ON BUT THE V TEC RIPS AT 5500 RPM, I HAD 2 ADD AN AFTERMARKET TACH 2 SEE HOW IM REVVIN, IT RUNS GREAT. ANY INFO WILL BE GREATLY APPRECIATED.

 

well first of all, chill with the caps, that's just rude online behavior, check the post about checking your ECU, or go to Autozone and have it checked out and they'll tell u everything that's up wit hthe CEL. VTEC is a unique code (21, and another i can't remember off the top of my head right now) and it does not necesarily mean that its right or wrong. you'll have to double check wiring and stuff on the dash harness side to your cluster.

 

check ur speed sensor located on your tranny maybe it is unpluged ?or busted clip or somthing

 

VSS disconnected would not cease the function of the Tachometer - I think his cluster probably got loose if he didn't change anything but the motor.