There's always some weird noise!

[Luke]

Well, i finally get rid of that timing chain rattle, and now im faced with some other annoying noises. Not too long ago I started noticing one noise kind of like a whistle/hissing. It only happens when i give it some sort of gas, under a load, like while im driving. It doesn't do it stopped in neutral that i can tell. I can't remember totally, but i think it does it more when the car warms up some.

I would be a retard and say it sounds like a turbo, but that's what everyone does when they hear a whistle noise from their car. I have even scared some random people trying to race me on the street and i had another guy asked if i had an sr. haha anyways. I checked around for vacuum leaks real quick, and didn't see any obvious leaks.

Ok, and more recently, i've been noticing a metal rattling under the middle of my car ( i think). What's weird is, it only seems to want to vibrate at constant rpms. Moreso, when the rpms pass by either 3k rpms or 2k rpms, it will do it, and i can hold it like that for a little while, but no where in between. I got under my car and felt/looked for loose heatsheilds and found none. I'm gonna jack it up in the next couple days to get a better look. I did notice that I guess the ground wire that is by the cat is hangin there(from the top of the car, disconnected from the cat, the wire was ripped). I wonder what that has to do with anything hehe.

Anyways, does anyone think that rattle could be an exhaust leak or something? Or maybe a rotted out cat? I've only got 100k miles. And could that whistle be linked to this other noise possibly? I'm looking for some ideas that's all. I also just replaced the water pump, what kind of noises do those make when they aren't working properly (my old one was leaking, i did a good job of replacing it though). Thanks for any help...

[SLIMMY240]

your power steering pump will make a whining noise if its low on fluid, mine does that a little from time to time, as for the rattle, all i can think of is the heat shields. they may not be loose but they could be flexed enough to were they vibrate enough at certain rpms. i noticed most of the rattles in my car at around 2200 rpms, and 2700, and aroun 3200-3300rpms. the best thing to do is get someone to step on the gas and hold it while its doing it and listen under the car, touch different parts (not while its hot) and see where the rattle stops.

[bj180sx]

heat shields were the pain in the butt for me. Just rip them off.

[ricebike]

in terms of that extra ground wire...

someone told me waay back that it was a redundant ground for the engine or it's to retard the rusting of the exhaust system...

i had a gasket leak @ the back of the cat to the pipe... then my muffler fell apart as well as the internals of the resonator... another member gave me his hardly used cat & hks system. whoo hoo:P