Doesn't matter if it's a warm or cold start, my 1994 maxima will start up at 14-15:1 AFR, then dip down to mid-high-11s, then go up to high 12s and finally stabilize at the 14-16 range a few minutes later. I want to avoid this for fuel consumption reasons, is it just because I have my wideband hooked up in place of the stock O2 sensor (without a resistor for the heater circuit so I do have a CEL, I have the resistor just need to solder it) or is it something to do with the MAF or coolant temperature sensor? How can it be avoided?