1. Check the oil level. Make sure the oil level is full. If the oil level is low, it can cause the lifters to tap.
2. Change the oil. Old oil can cause the lifters to tap.
3. Check the oil filter. A clogged oil filter can restrict oil flow to the lifters and cause them to tap.
4. Check the hydraulic lifters. The hydraulic lifters are responsible for adjusting the valve clearance. If the lifters are worn or damaged, they can tap.
5. Check the pushrods. The pushrods are responsible for transmitting the motion of the camshaft to the valves. If the pushrods are bent or damaged, they can tap.
6. Check the camshaft. The camshaft is responsible for controlling the opening and closing of the valves. If the camshaft is worn or damaged, it can cause the lifters to tap.
7. Check the valve springs. The valve springs are responsible for returning the valves to their closed position. If the valve springs are weak or damaged, they can cause the valves to tap.
*If you are unable to stop the tapping noise by following these steps, it is recommended that you take your vehicle to a qualified mechanic for further diagnosis and repair.*