You will still get a mil light if you don�t have them plugged into a properly functioning o2 sensor. All the mill does is altering the signal the o2 sensor is sending to the computer making it think the pre cats are working.
98.5 Black SVT with 34k miles Build #5683 Born on 4\15\1998
WR Headers GMK CAI
Blaupunkt system fiberglass tweeter pods
L.E.D. tail lights in the works
