tugalo

While you are checking your grounds, add one between the negative battery post and the front clip.....does wonders for the brightness of your headlights....

A couple of possibilities, remove and thoroughly clean all grounds and/or install HEAVY duty new ground wires. Add one between the battery and the front clip. Sometimes the sensors give bad info to the computer due to high resistance grounds. As for the cruise, there is a switch HIGH up on the brake pedal arm, it is hard to see and harder to get to...this switch releases the vacuum to the vacuum servo when you are in cruise and tap the brakes...if it is bad or out of adjustment, you will never get vacuum to set the cruise. Pull off the largest hose to the cruise vacuum servo and plug the outlet on the servo, if the cruise works, then you know something is wrong with the switch. Be careful if you do this cause you will have to turn the cruise off with the switch, the brake pedal will not cut it off. If you have an auto, the switch also has an electrical side that tells the torque converter to unlock. Good luck