I had the timing belts replaced, AEM cam gears installed, and trimmed the valve cover to make the cam gears visible. Ever since these things were done simultaneously, i hear a chirping sound in the area of the cam gears? Is this normal when replacing the timing belts? My mechanic said it would fade gradually until completely gone. I have run the engine for about 550 miles and it has diminished a bit but still is noticeable. It is mostly heard with the car at idle. Has anyone experienced this?

Thanks,
Mark