i have B16A2 engine, and the oil level is good and the water in good condition, engine temp was normal. i was running in a high way with 55 MPH i heard a knocking noise from the engine, i stoped my car and check my engine, every thing is normal, after that i continue driving the nise was disappear, after 6 hours parking i start my engine and nothing happen, after 20 Mile the noise come again for 1 min and disappear again, anybody knows this problem?

 

Check your belts.