Finally i got to work on my friends 01 cobra today. After new spark plugs, an oil change and adjusting the timing the car still has the same problems. I found some stuff out as i was working on it though. The oil had not been changed in a years time and spark plugs looked as if they were factory plugs, still wearing the motorcraft writing. We adjusted the timing to 12 degrees and it did make the car run stronger but only after it had warmed up. Car still bucks horribly when cold and has left all of us scratching our heads. Was there a recall at one time on the heads on 01 cobras? The motor does have a small ticking sound that sounds to me like its coming from the driver side head. Car runs good though when warmed up and ticking still exists. I dont know what it might be. Anybody have a clue?