My Noise Problem Identified
 

For those who have the high pitched noise coming from the engine compartment (not the ecu), the problem has been identified. The noise is
coming from the throttle bodies which are electrically controlled. I disconnected the harnesses and sure enough the noise stopped (also threw a code). Took this info to Nissan and he said that some of their other cars have this problem also.

Did i not mention to you about the throttle last night in my post? :)

great job! Hope Nissan can take your findings and do something.

Nice find!

Yep, I don't notice it when driving, but when you turn the car off, the "whine" continues for about 2 seconds after the engine shuts down, then fades out.

John

Interesting.....I noticed when I installed the Stillen grounding kit, that both TB's get a dedicated ground line...Maybe they know something Nissan does not??...
I thought about that for a minute and realized thet the TB's are mounted to a plastic mainifold and not grounded other than through their harness..I couldn't see where it would be more than a redundant ground, but maybe not..
No noise on mine BTW..

Modshack, Where did the Stillen ground get installed on the throttle body? Thanks.

A ring connector Under one of the 4 bolts that hold it to the manifold..

LOL one ring connector and wire shuts up all ringing, whining, and crying all together...(?) dang...

:yawn:

Err....well, we haven't determined that yet, but for those with noise, trying a simple ground connection might be worth the few minutes just to check..

I just tried it and noise doesn't stop.

I hope you don't also have the ECU noise since the TB noise is faint in comparison.

Oh thank God it looks like the problem had been identified. For a while now it had been a big mystery. It is hard to say if Nissan would fix this kind of problem. On the Warranty terms and conditions it says it doesn't cover out of place sounds, noises, vibrations, and what not. The attitude is, "If it's running fine despite the noise; then it is not covered under warranty". Kind of screwed up I know but that is just how it is with these Corporations. Considering how much money people spend on a 370Z starting at $34,000; it would be better if there weren't any of these noises that are out of place.

On a side note when I went to the Subaru test drive event near Malibu. I noticed that those cars performed flawlessly. There was not a single noise out of place at all. I wonder what had happened to Nissan.

For him it has been identified, there are still two variables in the noise. The one posted in this thread and the ECU in the other thread. Noises are bound to happen, this one seems a bit overlooked, but at the same time it is now a high "failure" rate as I will put it. Not everyone has it, so all internal testing could have come back fine, plus many are only having the issue after 5,000 or 6,000 miles.

............and the throttle body noise is minor, and cannot be heard when the engine is running and you are driving.......... the inside/ECU noise is an entirely different animal, and is hard to live with for those that have it.

It's hard to imagine that an ECU could make much noise at all. Unless it has an electric cooling fan, there are virtually no moving parts at all. Why should an integrated circuit flowing with a few electrons create any kind of audible noise to be heard? I can see why a Diode would make noise and in some alternators they do. I have seen relays make noise and they are mechanical and electrical. But I have never seen a computer chip make any kind of noise unless it were an electric cooling fan right next to it.

I had all kinds of cars in the past that made all kinds of different noises at different times. I never obsessed over it so long as the thing ran fine. I would just ignore the noises or cover it up with music from the stereo.

If it is in fact the ECU making noise. Maybe this problem can be solved by placing "dynomat" or some other sound absorbent material around the ECU to isolate the noise away from the cabin.

I was surprised, my gf's car makes the same frequency noise; but the noise was on the rear of the car. Hers is louder though and noise won't stop. She drives vw getta '08.

Sorry, I am new here to the 370z family, but noticed you guys have been complaining about noise coming from the car.. Was this noise identified when ya'll bought the car or does it slowly come about?