I just bought my first diesel and it's a 1999 Econoline box truck with a 7.3. On initial start-up of the day, it doesn't want to wake up easily. I have to sit and nurse it (patting accelerator, possibly restarting) for about 10 minutes before it will sit and idle by itself. Then I have to let it sit for 15 or 20 minutes before it's willing to be driven. I do not live in a cold part of the country. I live in Mississippi where it's very warm and humid right now. I see that this diesel has a LOT more stuff on it than your usual gas burner, and I realize a guy could spend a fortune replacing parts, which I don't want to do. The truck has almost 300,000 miles on it. When I bought it, I did drive it back home (2 hour drive) while pulling a car dolly with my Camry on it. So, while it did make the trip without issue, the temp gauge never budged much (didn't even get 1/4th the way up), and it ran smooth. I've read about the IDM, so I looked at mine. There's no corrosion or anything that would look suspect, but it does look to be original. I've ordered the inexpensive blue tooth scanner to do the buzz test, but was also hoping someone here could help with some advice. Your time and help is very much appreciated. I'm definitely a diesel newbie!