Honda Knocking Noise While Cruising
Suggested Repair
Pull the valve cover and inspect for a cracked cam tower or damaged piston skirt. Also check the nearby cam-belt tensioner and water pump. A rod knock would typically be loudest under light acceleration and load. Do not allow the timing belt to jump or come off.
Conversation Summary
A Honda owner with a built B16 engine noticed a knock near the cylinder head above the first piston after track runs and a missed shift. The noise is absent at idle and under hard acceleration in a high gear, but present while maintaining a constant speed; there are no leaks. The expert advised pulling the valve cover to check for a cracked cam tower or piston skirt and also considering the cam tensioner and water pump, noting that a rod knock is usually loudest under light load. They also warned not to let the cam belt come off.
