rattling engine noise under acceleration

amrarego, If your rattle noise is between 2000 and 3000 RPM typically, there is a TSB (Technical Service Bulletin) that applies - 04-15-04. This bulletin states that the noise may be caused by the primary timing chain tensioner system. The repair for this is to replace the Primary Timing Chain Tensioner, Chain Guide, Jackshaft and Crankshaft Sprockets with a Primary Timing Chain Tensioner Kit. The Kit includes an improved Primary Chain Tensioner, as well as updated Primary Chain Guide, Primary Jackshaft, and Crankshaft Sprockets. Required fasteners, Primary Timing Chain, and Front Cover Gaskets are also included. I am not stating that this is for sure what you are experiencing -- just that it is a fairly common issue from 1999 - 2002 on the 4.0L SOHC engine...and I've seen it several times before. Naturally, you could have a bearing problem or a valve train problem as well causing your rattling. You really won't know until you get a good hands on opinion. Good luck.