Check under the black box looking thing where you would put the oil in.
That black thing on top is just an engine cover to reduce engine noise. It's only held on by 4 little ball shaped guides on top of the engine that pop into rubber grommets on bottom of the cover. It's not too hard to take off just by pulling up hard on it, sometimes they seem to be stuck so just pull harder. Then just leave it off if you like until you can better give a location of where the noise is coming from.And see exactly what is causing the rattling.
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Crawl under the jeep and see if ant bolt nut is got loose.Also check heat shield for cat converter, this gets loose many times and cause same rattling noise.
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check all your exhaust clamps, and the bar that runs between the engine and tranny and lower bellhousing too. Also check if exhaust is rubbing somewhere, or has a loose clamp.
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Also check the muffler, if its got loose.
To Order car parts online:--To get heavy discount on car parts .Click this link below:----
http://technoanswers.blogspot.com/2011/05/from-where-to-order-car-parts-online.html
For car error code diagnosis click the link below:---
http://www.automd.com/diagnose/?amdcid=apwldrbrd1
Car no start:--
http://technoanswers.blogspot.com/2011/05/car-will-turn-over-but-will-not-start.html
