I just purchased a 2006 G35 automatic sedan with 150k miles. This sound only seems to happen at the top end of 1st gear. Sounds like something is loading up and then releasing. I am not noticing any issues from performance while this is happening.

I've been able to isolate it by switching to manual mode and holding it in first gear while driving slow. I can bypass the sound If I drive faster than normal in Auto mode or manually shift to 2nd gear early - so it seems to be a low speed thing. It only happens once then its gone until I've shut off the car for a half our....then it will do it again.

http://vid770.photobucket.com/albums/xx ... ahmld4.mp4

Welcome to NICO!

Bummer to hear about this problem.

Are you talking about that whip cracking sound? Weird that it only happens once, but it is damned loud. Where is the recording device? Inside the car? In the engine bay?
Does a hard shift or anything change in performance when it happens?

Assuming you bought it from a dealer, I'd take that bad boy back while its still under the 30 day warranty or whatever and have it diagnosed and repaired by an Infiniti dealership.

Thanks for the reply. The cell phone /microphone is inside the engine compartment right under the brake fluid reservoir. Yes, it is that whip crack sound....although, when you're there it sounds more like a ratchet clicking type of "loading up" then "releasing"....similar in sound to someone turning a socket wrench a full turn counter-clockwise(that's the load up), then just holding the socket end while quickly spinning the shaft of the wrench counter clockwise(the release).

I did some more diagnosing on the issue and found that I can make it happen repeatedly by turning off the car for a few minutes then driving again. I additionally found that I can also make it happen at the beginning of 2nd gear as well. So it happens at the top of 1st gear or the beginning of 2nd gear.

It does not seem to have any affect on how the car performs while driving fast or slow. I listened to when the sound was happening and there was no surge of power, loss of power or any odd vibrations....just the sound.

I bought it used, but I will be looking for a dealership to have it looked at. I wanted to take it to a non dealership place but I realize that this probably needs to be looked at by people who deal specifically with these cars. Just wanted to see if anyone might have heard of this sound to avoid the dealership.

I included a second recording of it from inside the car. So you might have to turn up the volume for the car interior recording.

http://vid770.photobucket.com/albums/xx ... ahmld4.mp4

http://vid770.photobucket.com/albums/xx ... 7wysrn.mp4

Update on taking it to the Coulter Infiniti dealership in Mesa AZ for diagnosis. They said the sound was coming from the Actuator for the ABS system.

They said they can replace it but it would probably make a similar sound because the ABS system goes through its self diagnosis every time on start up, and makes the load up /push out sound within 15mpg. Most of the time its supposed to be a quieter sound.

So I guess its just a loud actuator. I was actually surprised that the dealership didn't suggest that I replace it. Oh well, I guess I have a loud ABS system Actuator until the system goes bad or I get tired of the sound.

Good call Frapjap on taking it to the dealer. Sometimes it pays to go them in times of odd auto situations, cause they know they're cars...."plus" they didn't charge me for the diagnosis.

Cool man! Glad it turned out to be something fairly simple and of no real consequence. Turns out there are good dealers out there still, that is very encouraging. Best of luck with the car, I bet you're a bit relieved and happier to drive it everyday now!

Wow that's crazy... I've never heard of that. Nor do I know why the ABS would be active at all during normal acceleration.

I was going to suggest going from reverse to drive (and vise-versa) while parked (with the brakes on) to see if it made any noise.

The ABS isn't' activating so much as the computer runs a self diagnostic and activates the solenoids to make sure the solenoids are functioning. I had never owned a car with ABS before the S14. It does something similar and the first time it happened it was a similar situation and took me FOREVER to figure it out. I ended up reading a sticker in the car somewhere that just happened to mention it and it finally clicked that the sound was in the brakes and not the transmission.

My Altimas and my Sentra made that sound after hitting 5 mph on first starting up. "ABS self test" is what I found via research. I noticed that my Sentra was much louder than on my Altima coupe. However, I do not get that noise on my 370Z at all. If I do, it's nowhere near noticeable.