I put in the vafc with minimal problems and some DSM 450's which seemed to go in fine, I set the vafc accordingly, but the car runs rough at idle and throws a CEL, which read O2 sensor heater circuit malfunction. Is this cause through a wiring problem in the injectors? It feels like the car is missing while running, so I wonder if a injector isnt firing due to a wiring problem, although I could be way off. ???

 

did you use the resistors for the injectors

 

First check the O2 wiring harness, then double check your V-AFC wiring. It wouldn't hurt to solder your V-AFC harness (instead of using the splicers) if you haven't already done so.

What year did your 450cc's come from? What color are they? I'm pretty sure all DSM 450's are a peak & hold style, which requires the use of a resistor. Perhaps if you didn't use resisters in your install, there could be a lot of electrical stress causing problems. (I have no idea what electrical stress is, but it sounds good)

Good luck!