Hey everyone. My '96 T100 has 207,000 mi on it and served very well over the years. Lately I have been noticing some very rough running on cold starts. Admitidly I live in Wisconsin and it has been pretty cold as of late, but this is the first time I've ever had a problem. I put new plugs and wires on, new fuel filter, new exhaust last fall. When I start it up it almost acts as though it's missing....runs kind of rough, after about 2-3 min she purrs like a kitten no problem. Something else I've noticed is my milage has really went in the tank 15-16 mpg. Could the two issues be related? Any advice?? Does anyone know anything about the O2 sensor(s)? I've never replaced them as long as I've owned the truck. Could this be the problem? Any way to test ?