I belive its the connection tothe o2 sensor. it got melted and corroded a bit by leaning on the exhasut manifold. So I must rewire the plug on the harness. I chopped one off of another s13 from the yard and will solder and rewire it to my harness tomorrow. Ill let you guys know if it worked. yea My knock sensor isnt hooked up. good point about the cluth