Sorry I don't have an answer either, but I get a sound as well between shifts... (noticeable between 1st and 2nd) and it does seem louder when the engine is running cold like aalbert mentioned. I've been wondering about this myself. Its kinda like the shifting sound in that movie Fast and the Furious or some other movie... (or maybe it was video game, I don't remember). Anyway, I think it sounds cool, but I wonder if its normal or not. Any explanation would be appreciated.

 

yea i like it too but i just want to know if there is something wrong with my car so i can get it checked out when my car is still new and not when it gets more milleage. anyways hopefully were not the only ones experiencing this..hey Granet Canuck any insight on this

 

It isn't very loud, but noticable on mine as well, between shifts, under "heavy" acceleration. Sounds like it's coming from under trans tunnel, so probabaly either exhaust or transmission.

 

again....any idea of what it is officially?

 

Another shot in the dark: Gear whine from the transmission?.

 

maybe its the dual intakes sucking in air?? i get that noise on my coupe but i have the pop charger. i think its just more air. if im not mistaken doesnt the new sedan have dual ram air intakes?

 

dude sounds like a blowoff valve......woooo pshhhhhh wooooo pshhhhhh haha if thats the dual ram intakes then how am i the first person to post about this occurance?

 

maybe a sudden drop in temperature? maybe you're the first to really push the car "off the line" who knows? honestly to me if it sounds like air and you dont have any performance issues, its your dual ram air intake.

 

I had another thought.

I was installing a car starter (ok, helping) on an FX45 with a symptom that you describe.

It was tracked to a leak in the exhaust under the car. Very audiable from inside.

If it's cold, perhaps you could peer underneath and look for a small plume of mist/smoke? but if it's pointing upwards towards the car, you won't see much of it.

Btw, he isn't the first to try it off the line, all I can report is a glorious sound

 

My car exhibits this noise, also. It sounds kindof like the torque convertor. Usually this would worry me, but I don't know a whole lot about Nissan transmissions yet. It only makes the noise when the transmission is attempting to shift smoothly, not when it performs an aggressive shift.

Has anyone asked the dealer about it?

 

exactly what i am experiencing everyday...non agressive shifts that produce like a back pressure sound..i dont know if its a loose connection in the exhaust manifold, headers or what

 

To quote from another thread...

Smooth Lock-up Control
When shifting from the lock-up released state to the lock-up applied state, the current output to the torque converter clutch solenoid is controlled with the TCM. In this way, when shifting to the lock-up applied state, the
torque converter clutch is temporarily set to the half-clutched state to reduce the shock.

I wonder if this is what is happening when we hear that sound.

Anyone care to chime in?

 

i hear it too, i like the sound happens on the shift between gears most pronounced between 1 and 2 but if you listen close you can hear it on the 2 to 3, ditto on the more cold the more loud the sound also.

 

Yes, I have noticed the same "blow off valve noise" in my G. I have an automatic as well. Definitely requires that the shifts are above 4k RPM, and I can hear it when shifting 1st to 2nd, and 2nd to 3rd; bit too much wind noise to hear it from 3rd to 4th

It really does sound like a pressure relief valve blowing off when the RPM drops during the shift, and it doesn't seem to matter if I'm going at WOT or slowly getting to 4k-5k RPM, although the latter is much more difficult to accomplish So far the car has been running smooth, so I was waiting until my first oil change and ask about it at the dealer.

Maybe we'll get to the bottom of it one day.... keep those throttles open.

 

Yup! I can Confirm I have this Noise also, and mines is a 6MT. It's is more Noticeable On the 1-2 shift. not too much on the 2-3 shift, its wierd sounds like a blow off valve, LOL. But really Wonder what this sound is? Can't be the Trans,. Maybe some exhaust area? or a Vacum leak somehwere? Does not Bother me too much, if it does I just turn up the Stereo! LOL., Hope we Find a solution or at least know what is making the Sound