This initially happened about a month and a half ago. I was parked at a store and went in to grab some items while my wife waited in the running / idling car, A/C running.

I came back between 5 & 10 minutes later and pulled out. As I went over a bump, I heard a mild creak. As I went over subsequent bumps, the creaks got louder and more horrible - pretty much a cracking noise loud enough to draw attention to anyone standing by as I went into and over small dips bumps.

I immediately went to the local Nissan dealer. I had to wait for ~ 20 mins for a tech to go on a test drive. Vehicle was off during the wait. Tech was finally free and hopped in the car with me and the sound was gone and I couldn't replicate. I felt like a retard.

Since then, it's happened two more times and I think I've isolated the occurrence to idling the vehicle for at least 5 minutes in very hot weather (>80*)

My initial thought on a culprit is fluid motor / transmission mounts or potentially ball joints of some sort but I honestly have no idea.

Has anyone else experienced this?

Edit: This is on an 07 G35S AT

 

I have had heard these noises before, but only when my a/c has been on and running for a while and I come to a stop then go over some bumps.

Have you noticed this when the a/c is off?

 

I haven't replicated the issue by leaving the A/C off - have you been able to track it down?

 

I have had this happen. Also when it was very hot, but I can confirm it did it w/o the AC on too. I just figured it was the sway bar bushing or something similar occasionally getting sticky from the heat build up. Once things have cooled down again, the noise has always gone away, so I never persued it's origin. If it ever stuck around, then I'd worry about it, but until then, not so much.

 

I haven't actively looked for the noise, maybe it was because with the a/c on maybe its gets hotter or something.

The noise was never there without the a/c on, but I have also been listening for it numerous times since then with the a/c in either position and I have not heard it like I did that one time.

It sounds similar to what you were describing but could have been a one off thing, maybe something up front got some dirt or debris in it and eventually came off.

 

Okay. It's somewhat annoying / embarrassing having the car cracking and creaking after having idled in the heat for just a few minutes. However, like you said, if it persists then it's something to really worry about.

If I do decide to take it in (which I just might this weekend - local Nissan dealership has a detail deal for $20 including clay and wax) I'll post what the outcome was. Thanks.

 

Guys, this noise has been haunting me for about a year now! The dealership wasn't able to reproduce it like 4 times, so I really do look funny now asking about this problem.

I was able to hear this noise when it has AC running, then parking the car and gently liffting and letting down the left front fender - definitely can hear the noise. Without the AC on not in the hot weather, this noise can hardly be reproduced.

It is quite loud and embarrassing.

Anyone got a solution?

Thanks!

2007 g35x

 

When it happens take out your phone and take a vid., park your car and take a video , maybe they won't look at you crazy lol. see there simple

 

also check out your muffler system, well the hooks and the rubber thing. sometimes when its really hot it shrinks or gets loose kinda and makes that annoying rattling nose underneath.

 

I did make a video when this was happening so they said - "..we can't replicate it right this moment so we cant' diagnose it."

I'm kinda tired of it and want to fix it myself. Especially considering the fact that I do quite a bit of maintenance on my cars myself.

 

Thanks. Sadly enough, I don't think it has anything to do with my exhaust.

The symptoms are exactly as described in the original post:
- hot weather
- AC running for awhile (not necessarily idling)
- about 10 minutes into driving and while going over some minor bumps this loud creaking noise appears
- noise stays until the car is turned off and cooled somewhat

It's actually pretty loud and hard to ignore. I tried for awhile but now committed to making go away

 

Fix it yourself. for real though check your muffler system. Its probably either a broken hook or the rubber is loose. reason for it getting louder is the vibration on your engine

 

I feel you on that one. It is definitely annoying.

My car did this to me again the other day. When I pulled into my driveway I could very easily reproduce the noise over and over.

My only thoughts are that when the a/c runs, some things get very hot from the heat exchange and others get cold. If a bushing or restraint on something gets cold and shrinks, maybe the item it is holding does not fit snugly, therefor it makes these noises.

On the other hand, maybe the under hood temperature gets so hot that something loses its rigidity and starts to flex more than normal, giving us this noise.

Once my car sits for like 20 minutes the noise is gone and unless its very hot and I run the a/c hard, it wont make the noise again.

Weird huh?

 

Thanks! Sounds much like something I have. My suspicion is a wornout rubber bushing somewhere in the suspension and near the AC where temp ranges are taking place.

I'm going to have to choose a hot day to idle a car, then jack it up and rock it gently to see where exactly this is coming from. This seems to be coming from between the front left wheel and the firewall though.

 

I have the same noise occur on occasions when it is hot also. As a matter of fact, just today, seeing as how it's 105* here.

I have gotten it without the AC running, but usually when it has been hot enough to make the noise, I'm running the AC, so I'm not sure which comes first or whether AC is truly a required component in triggering it. AS mentioned before, I also suspect it is some suspension bushing that gets overheated, possibly due to proximity with AC (compressor/lines/condenser ), and my first guess would be the front sway bar bushings. Since it always goes away once it cools, I've learned to live with it so far, but if I ever got the urge to troubleshoot it, I would definitely start with spraying some lube in the ends of the sway bushings and seeing if that affects it; next would be the end links.

If it's bugging you enough, I'd say go for it and report back with the results; quite a few people could use a definitive answer. Usually when it's that hot though, the last thing on my mind is jacking up the car and crawling underneath all that hot mass.