Put the ignition switch on (without starting the car) and make sure the car is in gear (manual) and you can hear the noise coming from the engine bay. Putting the car into neutral stops it so that should be a hint as to what is causing it.

The sound is so high pitched and loud you have no problem hearing it when you are driving at freeway speeds with the radio on.

Wrong, the sound only happens when the car is under power. As soon as the car stops the sound stops. If your parked and rev the car up you hear the sound. The sound does not change with RPMs, it's either on or off.

It must be two different problems or it acts differently in the automatic.

Whatever is causing your issue is not the same high pitched sound we have all identified then. Ours is faint, coming from under the engine cover, dates back to the G37, fades out when you turn the engine off after about 2 or 3 seconds, and cannot be heard once the car is running.

John

It is totally different, my car makes no noise when the car is stopped, only while under power.

Catching up on the thread. It sounds like there have been other noise complaints in the past, but please don't assume our problem is the same.

I wouldn't say the tone gives me a headache (I get the impression Roo's sound is a bit louder than mine), but it's loud enough to make my ear itch if that makes any sense at all. It's like the ringing in your ears after firing a weapon without ear protection, or coming out of a loud concert. No amount of other sound covers it (engine, radio, etc), but if loud enough the tone is easier to ignore. Anyway, this has all been said before.

I'll have more data Thursday.

Exactly, this is not so much a noise but a ring. Even if you turn the radio up you can still hear the ring since it is a different frequency.

Yep, tried this, and this is exactly what it's doing. It's weird when you put it in neutral it goes away. Maybe something to do with Syncro Rev Match???

I'm going to dealer next tuesday to have them replace a door panel that split, I'll have them look at this as well. :tup:

Ok I've been reading this thread and it sounds like there are some vehicles that have some significant noise coming out of them. I think if the people who have the problem state the exact configuration of their vehicle it would be easier to diagnose what is going on. There isn't enough info in this thread to see a common theme....

Is it possible there is some sort of switching power supply in the vehicle? If you add to the electrical load does it get worse/better? (eg turning on all the lights, high beams dome lights - not the stereo though since that would mask the sound levels).

Don't discount an exhaust leak either. They can make all sorts of weird and crazy sounds including whistling, screaching, etc.

G'Day all from Sydney,Australia::happydance:
I am the proud owner of the all new 370Z,only just arrived in Australia just weeks ago.
Unfortunately,I too have the same high pitched noise that some of you guys are experiencingNOT HAPPY!!...:mad:the bomb I traded didn't cause me a head ache to drive!!!
I can also confirm that the noise is coming from under the glove box.I know it is not the radio,speakers, GPS, air con., mobile (cell) phone:confused:.My Z is auto, right hand drive.Nissan are checking it out tomorrow.Thanks to this site,:tiphat:I know I am not the only one with this prob.Lets hope we can all get it sorted with out too much hassel.:driving:

I have good news. The tech positively identified the sound as coming from the ECU itself. No suprise that the ECU is in the dash behind the glove box.

They have a couple 370's on the lot that could donate an ECU temporarily, but they are 6MT. Unsure if there is any difference in the ECU between 6MT and 7AT, they are playing it safe and ordering a new ECU overnight shipped. I hope to get my 370 back tomorrow, sans high pitched tone.
:werd:

Roo, I'd add that you should be very disappointed in the techs that looked at your car. Doesn't sound like they tried too hard.

I am taking your info 2bits to my dealer and having them do it. I leave Sunday for 3 weeks so I'll leave the car with them and tell them I want it fixed.

Got my car back today, and I consider this issue resolved. The new ECU isn't perfectly silent, but it's good enough. I can hear the sound when the cabin is quiet, but even then it's pretty subtle. The other 99% of the time, I forget about it completely which wasn't possible previously. If I hadn't been so annoyed by the sound over the past couple weeks, I wouldn't be listening for it and probably would never notice.

Good luck Roo and anyone else who get's a bad one. Fortunately, it's an easy fix which only requires removing the glove box and programming the new ECU to work with your existing FOBs.

Nice job figuring this out. + rep