Cold Start issues

[vrt93]

Its gotten colder recently (cold for Texas so like 40-50) and I've been noticing, in conjunction with the voltage drop from the grid heaters causing a little dip in idle RPM, occasionally the RPM will dip or surge on its own for maybe a second or two while I'm letting the truck warm up. Today, I had to run home from work to take care of something at lunch and I didn't let it warm up totally before I took off. As I was leaving, the RPMs dipped again and the truck just shut off. I was going downhill in a parking garage while this happened, trans in neutral, not holding the clutch in or anything. I've read that it might be the fuel control actuator/MPROP but I wanted to get a second opinion before i bought the part