96 4runner 1500-2500 rpm rattle: HELP!

[ulricr]

Ive got a 96 4runner(auto). it runs great except for a rattle that seems to come from under the truck, right about the driver seat area.i can hear it when i go up a hill, when i accelerate, any tiem the rpm hits 1800 or 2200. it sounds like a drumer hiting on an aluminum plate. i checked all the heat protectors i could see, and it just passed a mechanincal inspection for me to get it plated, and the mecanik didnt see anything wrong under the truck. WHAT COULD THIS BE?

HELP!!!

 

[lmass]

it might be the heat shield coming lose that is causing your rattle.

 

[amagalla]

It's possible that your catalytic converter need to be replaced. The plates in there sometimes break loose and rattle. It's under the passenger side in a 98, but it might be different on yours.

 

[ulricr]

yeah thats wht i thought. the cat, ill check it fo sho!

 

[shootmymime]

how many miles? around 200K? if so its a exhaust leak, the bolts on the intake manifold heat and cool hundreds of thousands of times over its life span, thus creating a gap on the exhaust manifold and the heads of the 4runner. and that noise is the air escaping threw the hole. i have seen it many times in older cars, and

infact my 96 has the same thing, but mine sounds likle its comming from the driver side of the engine bay, and its around 2500 RPM...

i belive the way to find it is to tighten all you exhaust bolts down and see if that is your problem

 

[Casper]

while you are tightning things...check to ensure that your 02 sensors are tight. I had one back out on my GTO and under certain rpm and loads, it would rattle.