I have a metallic ticking noise from my engine. Have replaced the Oil and filter and removed the tappet cover to see what happened. One of the rocker retaining springs came loose from a rocker (It seems a hydraulic lifter siezed, causing a valve to drop a few millimeters and loosening the tension on this spring -- This is all on the Intake side of the motor). The retaining spring has carved a 2mm deep line on my intake camshaft which will need to be skimmed smooth again. After reseating the spring and rocker, the valve below this rocker was still dropped by 2mm or so. I suspect the valve may be bent. I have not removed the head as I don't have the BMW tools; I don't know the state of the valve seat. All other valve springs are at the correct height. Please give a quote as detailed as possible, splitting the engineering cost of the camshaft from the head, etc. If possible, I need this to be fixed where the car is, moving it is not entirely an option.