I just had the same prob, it would click once, and nothing, chaged out starter and still the same prob, check all your grounds, and clean them, make sure to check the one going from the block to the frame, Should be the one on the head on driver side, or on the water pump, You can use some jumper cables, and ground one end to the block and put the other to the neg side of the battery and see if it cranks...Make sure all your conections are good and tight.. Also test and see if you are getting 12v to the starter itself...