I did a number of tests to ensure it's whenever the engine is at 1500rpm.. I put the car in drive and gas up to 1500 and there's a clanking/grinding kinda noise. I put the car into Neutral and do the same thing.. again same noise.. It's not the tranny I don't think

Any feedback? it's sounding more and more horrible everyday

 

anyone have ne idea?

 

my car did that same thing at about 2500 rpms, does it sound like a couple of metal pieces rubbing together real fast, kind of like a TWIING noise.... on my car the bolts that hold the heat shields onto the cat conv rusted out, and the shield was loose, when the engine hit the perfect rpm it would cause the loose sheild to vibrate and make this god awful noise.... cut the heat shield off... noise stopped just like that.... check all your heat sheilds, make sure they are tight, if they are rusty and or loose, find a way to tighten them down, or remove them all together.

hope that helps, hey if i turn out to be right drop me an e-mail

boxxer@chartermi.net

 

yea that sounds like my problem, but my cat is where the header is, it's a '98 Lx, and yes I know doesn't have vtec but my other car does lol..

and I tried to track down the source of the sound, sounds like something under the valve cover, like a couple of metal pieces rubbing together as you said. Somewhere under the Throttle Body, or around that area..

Any heat shields there?

 

not that im away of, under the valve cover huh, well check around it, any metal piece that could vibrate would do the same thing, especially any part thats mouted to the body, while the engine is free to vibrate around in its rubber mounts.... if you think its INSIDE the valve assembly, take the valce cover off.... take a look inside, just make sure to get new gaskets and reseal it properly

 

mine did the same thing around 3500-4000rpms

loose heat shield. I work next to a garage, and they found it and removed it. no more noise.

 

I hit a stealth ninja speed bump at like 40mph, and it loosend my heatsheald, i just replaced the broken screw and its fine now, this was around 2500rpm.

 

I'm starting to think it's a heatshield rattling, maybe one underneath the motor where the exhaust piping is.. my buddy mentioned this kind of problem before on his car.. he put an extra clamp to hold the heatshield in place or together.. I can't remember exactly.

while I was driving today.. I noticed that when the car was cold, or just started driving, there was noise at all.. but once the car's warm the noise came back.. so maybe the heatshield expanded and caused some vibration between the bolts or something..

Here's a pic of my buddy's heatshield, he used a clamp to hold the top and bottom heatshield together..

This sound familiar to anyone? I'll take a look at my car once I get the chance to.

 

sometimes the heat shield needs to be bent further from the exhaust... my car had an annoying rattle, at 1,200 RPM... i thought the exhaust bolts needed to be tighten, it worked then later on it rattled again, but eventually i found the exhaust rubbed against the heat shield, and i put a breaker bar between the exhaust n' shield n' pulled them apart the bend the heat shield away from the piping and it solved the rattling problem.