I have a 1993 Chevy S10 with a 4.3 TBI injection. About a month ago it started loping during cold start for the first few seconds. It had a code for the IAC and the Knock sensor so I replaced them but nothing changed. I replaced cap, rotor and wires and it made it much better (for a few day) Checked codes again and I still have one for the IAC. All the wiring looks good and all my reference voltages to the sensors are correct. This morning I had to rev the engine for about 2 minutes before it would idle smoothly and it was about 70 degrees outside. Anybody have the problem before?