Place chili powder, garlic powder, sugar, salt and pepper in a 1-gallon ziplock bag; shake to blend.
Add pork tenderloins to bag. Shake and massage until they are well coated. Seal the bag and refrigerate for 2 to 24 hours.
Prior to grilling, melt apricot preserves in saucepan over medium heat.
Remove pan from heat and stir in remaining glaze ingredients.
Place half of the glaze in a serving bowl and hold for service.
Prepare grill at medium-high heat. Grill pork tenderloins for 15-20 minutes, or until the internal temperature of the pork reaches 155 degrees F on an instant-read thermometer.
When approximately 4 minutes of cook time remains, brush the pork tenderloins with the apricot glaze remaining in the pan. Cook for 2 minutes, turn the pork tenderloins and brush glaze on other side. Cook for an additional 2 minutes. Remove pork from the grill and let set for about 5 minutes before slicing. Serve with reserved glaze.