My son has a 98 Dakota R/T w/ a 5.9 Magnum. About 3 years ago, in the dead of Winter, it wouldn't start. It would crank just fine but just would not fire. He was living in an apartment and needed this truck to go to school and work so this created some serious issues for him. Since he had replaced the plugs just a few months earlier during the Summer, I first assumed they were good. We tried various tests and everything seemed to be fine with everything else. Mind you we were working outside in about 10 degree weather and after a couple hours, I packed it in for the day.
Then I just did what I always told him, start with the basics, assume nothing. I got the Champion spark plug number from the underhood emissions sticker and on the way to his place the next day, I stopped at a parts store and bought a fresh set of the Chrysler recommended plug. While changing the plugs I noticed that he had put in Autolites and he said that specific number was recommended by guys in the Dakota R/T club. Comparing them side-by-side it was obvious the Champions had considerable more reach than the Autolites. It immediately fired right up like it was summertime. Apparently, the short reach combined with the cold weather was what made the difference. I always use Champion plugs in my rolling junk.
Happy Ending.
He graduated and now the truck is his summer play thing again and only sees nice weather. It's run a 14.20 which isn't bad considering it's 4000 lbs.
The End.