2007 Camry LE, 4cyl -- Whistling sound from the engine?

[Kumba]

Looking to see if anyone has thoughts on this that I can either address myself or get the dealer to fix.

Over the last 10,000 miles that I've driven, I've started to hear this "whistling" sound that I believe originates in the engine compartment. I believe this because it changes in pitch with the rise and fall of engine RPM, mostly in speed, but quite noticeable if you flare the engine while in neutral. It doesn't sound related to the transmission, as the pitch stays in sync with the tachometer. It's most noticeable between ~50mph-70mph, before the pitch rises above the threshold of human hearing. At times, I can hear it while around 30-45mph, too.

I thought at first that it was the air filter box being loose, but I and the dealer both checked that at the last service appointment, and found nothing wrong. After that appointment, the sound was gone for a couple of days before it came back. Now I'm wondering if I might have something wrong with a piston in the engine (perhaps one of the piston o-rings?), one of the other engine hoses, or some gasket somewhere.

I could take it in for a noise diagnosis, but with dealers being what they are at times, coupled with the double recalls going on, I don't want to spend time (or money) having them "guess" at what the problem is. So I thought if I could get some advice on things to look at/inspect, when all this snow melts (DC area just got hammered with 20"-30" of snow), I might pop the hood and poke around. If I can find something, then I'd go back to the dealer with the specifics and have them address it.

Thoughts perchance?

[gdanaher]

Piston rings don't break unless you are driving at Indianapolis or Daytona. A whistling sound is likely just that, and probably generated by a loose or cracked vacuum hose. Since these engines are drive by wire it isn't as easy as it used to be to rev the engine while your head is under the hood. Get a helper to rev the engine to the point where the noise is audible and go about finding it. If you have a long piece of rubber tubing you can use it as a stethoscope. Keep your hands away from any belts or fan blades.

[JohnGD]

Could these two be the same problem?

Hissing noise from my 07 camry

[Kumba]

Okay, I figured it part of the way out. It's not a vacuum leak at all. I had it in for service today, and Toyota couldn't find anything. So I'm driving home, and I usually listen to a police/public safety scanner a lot. My new one, a BCD396XT, when plugged into the AUX input, makes a noticeable "popping" sound when the speaker cuts on and off between transmissions. Because I have a bad habit of picking up on sound patterns, I began to notice that whenever someone was transmitting, I could hear this variable whine coming from somewhere in my car. Turns out, I was hearing it from the car speakers. I *think* my engine is creating some kind of RF interference that reveals itself as this high-pitched whine, but it is only audible when squelch is open, and I have the scanner plugged into AUX. Now, I am using a really cheap male-to-male headphone cable. Do I need to get a beefier/shielded cable of some kind? Or might this still point at something odd in the wiring in my car?

[gdanaher]

If you only hear the sound through the headphones and not through the car speaker then a choke might help. Radio Shack usually has some ferrite cores that split so you can wrap a small wire through a few times and then snap shut. The RS guy will typically be an idiot, so search the catalog first to get the part number.

[Kumba]

Originally Posted by gdanaher

If you only hear the sound through the headphones and not through the car speaker then a choke might help. Radio Shack usually has some ferrite cores that split so you can wrap a small wire through a few times and then snap shut. The RS guy will typically be an idiot, so search the catalog first to get the part number.

Not using headphones while driving (that's illegal). I run a headphone cord from my scanner's line-out jack to my Camry's AUX-in jack, so I am listening to the scanner via the car speakers. I'm thinking I probably need something with a ferrite core for that, just wasn't sure if there were any other ideas from a car-related perspective. I.e., is it normal to pick up the RF emissions from a motor, especially one as large as a car engine (unless that's the altenator I'm picking up). I'm a member over at the RadioReference forums, so I'll bother them about the proper shielding on the wire.