Fluttering Noise when idling

[rosscoe21]

The past few days I have noticed a light, faint fluttering noise when idling coming from the engine bay. You can't hear it outside the car when the hood is up, just inside. Anyone have any ideas?

[repiv]

It could be anything but I'll put these forward. Things that can only be heard while inside the car only means that when under the hood, the various normal engine noises muffle it out.
Things that could "flutter" ......................
- Idle Air Control solenoid. When you hear it, go out and open up the hood and put your hand on it. It's the thing on the left side of the intake manifold just behind those "U" shaped coolant lines. It'll have a wiring harness plugged into it. Do you notice any weird idling characteristics?
- Clutch TO bearing. Test this by engaging and disengaging the clutch when it makes this noise.
- Valve train noise. How's the oil level? Use a stethoscope to listen at all 16 valve locations on top of the valve cover. If one valve is "off", you'll hear it.
- Small exhaust leak.
- loose "something or other" under the car that only vibrates at idle resonance.

You really need someone to listen to it first hand. Diagnosing sound on the internet is like explaining color to a blind man.

[rosscoe21]

Thanks for the help, you do an excellent job because I believe I understood your explanation of color. The noise does stop when I press on the accelerator. The oil level is okay, I just had it changed and checked it the other day so we can check that one off. The car only has 30000 on it. Is it possible it could be a valve.

[rosscoe21]

By the way, it seems to idle fine, it doesn't do this all the time, it seems like it does it when I drive it hard.

[darkside]

A valve adjustment wouldnt hurt.

[repiv]

A valve adjustment wouldnt hurt.

Only if it's done right. I've seen so many guys go get a valve adjustment or do one themselves only to screw it up far worse than how it started out. If it ain't broke, leave it well enough alone.

[darkside]

True , but I was posting giving the man credit enough to do a valve job or take it to someone who can. But reading once again you say you cannot hear it outside only inside, so that maybe not the problem.