I can't seem to identify this nose!
 

I'm usually pretty good at figuring out noises. However, this has me stumped. It kind of sounds like crickets! At first I thought Accessory drive belt. Changed it. No difference. Then thought about idler pulleys. Had my shop check, and was told they were fine. In fact they said they couldn't even hear a noise.
I'm not crazy. When I pull into an enclosed place, or pull up next to another car, it's plain as day. Not loud, but definitely there. Off idle, it goes away. It's not rhythmic. sort of random. The pitch even changes. It's driving me nuts! Anyone have any ideas? I'm getting tired of paying diagnostic charges, and being told they couldn't find anything!

A loose spark plug can cause chirping or noise and although it would seem to be tied to RPM if it doesn't chirp every single time it could seem pretty random. Would be pretty easy to check that all of them are torqued down properly. My son's Miata had a weird noise recently that we couldn't figure out and then when he was driving it blew out a spark plug... Reinstalled it and torqued it properly once the car had cooled down and no more weird noise...

I will second the spark plug theory. Mine never made noise on idle though. Only when I put a load on the engine did I get a noise. Like about every time I took off in first gear from a stop. I would get some funny looks from bystanders :eek:

I hear kind of a "crickets chirping" noise on my 2001 2.7 box when the engine is under full deceleration and the rpm are high enough to cut combustion. Didn't really know it may be a problem - (maybe I'll need to add checking the torque on the spark plugs to my to-do list to rule out that possibility.)

The car is still fairly new to me, and there are other more annoying sounds that I'm trying to diagnose - in particular something that sounds like a rattling heat shield, which only happens in certain RPM areas when the engine is warmed up. There are also some "ticking" sounds which I believe are small exhaust leaks. (Some I've verified are at the clamp joints by the muffler.). Then of course the aftermarket muffler is causing some pretty loud drone. Despite all those noises, it does still sounds awesome when you get the RPMs up! Another coping technique is to turn up the stereo, which sounds great. :)

Had same noise. Couldn't ID it. Heard it if I drove close enough to buildings.

Finally drove over an overpass that has a cement barrier between the street and sidewalk. Heard it loud as day. Then if I touch the brakes it immediately goes away. It's the front pads squeaking like some bad tricycle wheel, repeatedly as I cruise down the road.

Have to resurface the brake pads. That usually stops that for a while at least.

It could be surprising that the only thing that retracts the pistons that press brake pads to rotors is the flex in the rubber seals through which the pistons move. That rubber can lose flexibility without necessarily leaking brake fluid. In the best of circumstances, the clearance created by piston retraction is really small.

Thanks!!

I'll order a set. When a put a screw driver through one when painting them, the old one was very old & thin compared to the new one. I think they called them dust covers.

The spark plug theory sounds plausible. Now that you mentioned that, It started after I had the seals and plugs replaced. it also only happens when the car is warmed up. Guess I have a project this weekend.