Elbow cracks loudly when i tense and move it. no pain, but sometimes stiff. has since i was hit by a car on that arm years ago. can it cause problems?

Cracking joints: Painless cracking of joints is common. Some people can reproduce cracking joints by doing certain maneuvers, like cracking the knuckles. Painless joint cracking is usually caused by either tendon or air movement around the joint. If there is no pain, I wouldn't worry to much. Stiffness may be from repetitively cracking the elbow, so try to avoid voluntarily doing this and see if stiffness resolves