Hi everyone, I started hearing a loud ticking sound when I first start my car, a '97 Civic with 68,000 miles. This sound appears after the engine idles for a few minutes. I can hear it more distinctly if I kneel and listen from below. After 10 minutes of driving the sound disappears, and the engine sounds just right when idling. I don't think this is "piston slap" because it's much louder. I also checked the oil which was fine. I also checked all other fluids and they were in norm. A few months ago I had the idler pulley replaced with a new one. My mechanic suggested I replace all three belts some time. Can this ticking be attributed to the timing belt alone? Is there a point in replacing all three? How much of an expense am I look at? Any advice is much appreciated.