One of my buddies that is a Nissan technician said that my engine is knocking when it first warms up, and then stops. He said he couldn't tell me what it is without really looking at it. Does anybody know what it could be? I tried looking up "Engine knock" on the web, and all I've found are articles on using the proper octane. What do I have to do to remedy it? Do I have to do a complete rebuild? Thanks!

 

piston slap

 

Take the flat end of a screw driver, or a peice of hose. Place one end around on different parts of the engine, and head while it's idling. Then place the other end against your ear and listen. Sometimes this helps in tracing down noises...