Hissing sound - not quite an exhaust leak type sound - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

Albert88 · 09-25-2016, 12:46 PM

Hi All. Got my 2015 Camaro LS Manual about 2 weeks ago, love the car.

I've noticed that while accelerating I hear a hissing type sound after about 3K RPM. This doesn't sound like an exhaust leak, it sounds different...like a combination of exhaust leak, and an exaggerated sound of liquid being sprayed at high pressure. Couldn't think of a better way to explain it.

Do any of the V6 guys hear the same type of noise when accelerating, or do you hear pure exhaust? If it helps, the sound is coming directly from where the engine is sitting.

zenben · 09-26-2016, 12:52 PM

I have two things for you.
I have been chasing these types of things for the last 18 months on my 2 year old 2015 2LT RS manual.

1] The first sound was a snap-crake-pop rice-krispies kind of sound that comes from the glove box area. Based on what I have read this is something related to how coolant moves through the heater core. My dealership at one point removed the debris filter for the coolant and that seemed to eliminate this periodic sound for about 600 miles...but then it came back. My dealership said they bypassed the heater core and experienced the same sound. I'd have to see what they did with my own eyes...but since the sound didn't go away, they said this is "normal operation noise".

2] The second more annoying sound is a metal rattle, hiss, chatter sound that comes from the center tunnel area/behind the mylink screen. It happens at 3200RPM and 51MPH most of the time. Also whenever accelerating in most gears, as the RPM's sweep up through the 3000 area it will briefly make this sound. The dealer SUCCESSFULLY found that it is heat shield material way up and in underneath the car near the floorboard that is resonating when the car is making vibrations in that 3000-3300 RPM zone. It is the same type of corrugated-looking-silver-aluminum foil color material that you can see when looking under the hood that is attached to the engine bay. They tapped around all over underneath the car and found pieces that when tapped made a very similar vibration sound as what they heard when we went for a road-test together. They said the pieces they adjusted are very hard to reach...not reality visible. They repositioned pieces and I am quite happy now. It's rare for the sound to occur and now it only happens a bit sometimes in 4th gear and in a much more narrow speed range. The sound has also moved a bit more towards the driver and away from the center telling me that they are definitely adjusting the right materials. Not nearly as constant as it used to be. The car sounded like garbage when accelerating having this rattle chatter sound overshadowing the engine coming to life. IT's pretty darn great now!!
My dealership, Arroway Chevrolet in Mt Kisco NY is fantastic!!

zenben · 09-26-2016, 01:33 PM

In one of my visits, they did discover that there was a broken weld on a heat shield attached to my left side Cat. So they replaced the left side cat...but most of my noise was coming from the right so that didn't fix it. I can tell you from what the head of the service department said...who was the one who actually finally put his hands on the car to make the adjustments said the shields he adjusted were way up underneath the car...not part of any pathway that exhaust or cats occupied. They had previously on like 4 other visits adjusted all of those numerous times not leading to a fix.

rnikolich · 09-26-2016, 07:54 PM

I have this noise on my A6 as well. At first I thought it was something wrong with the gears in the transmission, but I assumed it was the heat shield around the transmission tunnel area because the car runs perfectly and I only hear it under harder acceleration or when messing with the paddles.

zenben · 09-26-2016, 08:35 PM

It's the worst sound!! It makes the car sound like garbage! I had some 4 cylinder sedan for a rental recently and admired how when I accelerated all I heard was it's engine, anemic as it was. But Now that mine seems to be fixed it's like having a brand new car again. I'm lucky I had a committed service department that didn't shoo me away.

derek1387 · 09-27-2016, 05:40 AM

I have this noise.....is it bad?

I cant make it stop.

Albert88 · 09-27-2016, 01:57 PM

Car has been dropped off the to dealer...if they can't figure it out I'll print out this thread and hand it over. Especially the video of the turbo.

Kenny Camaro · 09-27-2016, 02:26 PM

Quote:

Originally Posted by derek1387

I have this noise.....is it bad?

I cant make it stop.

You might wanna have that looked at, sounds like something 'bad' is going on! Lol

Albert88 · 09-30-2016, 08:49 PM

Dealer said they couldn't reproduce the sound. I told them the tech needs better hearing aids. The sound is very clear and very present. I'll try again on the next oil change. My only issue is that they drove the car for 10 miles and did "hard accelerations" to try to reproduce the sound....They'll have to do it again. This time w/ me in the car.

BLURPLE2 · 10-10-2016, 05:58 PM

I have this hiss on my '14 V6 automatic after getting up over 3K RPM. I had a small confirmed leak on the passenger side at the clamp just after the cat. replaced it and didn't hear the hiss for a few days but its back. gotta get it back up in the air and recheck..

ShadowYYZ · 10-13-2016, 07:34 AM

Quote:

Originally Posted by Albert88

Hi All. Got my 2015 Camaro LS Manual about 2 weeks ago, love the car.

I've noticed that while accelerating I hear a hissing type sound after about 3K RPM. This doesn't sound like an exhaust leak, it sounds different...like a combination of exhaust leak, and an exaggerated sound of liquid being sprayed at high pressure. Couldn't think of a better way to explain it.

Do any of the V6 guys hear the same type of noise when accelerating, or do you hear pure exhaust? If it helps, the sound is coming directly from where the engine is sitting.

Do you have a video? I experienced the rice crispier sounds.. still therr

Albert88 · 10-13-2016, 10:21 AM

Quote:

Originally Posted by ShadowYYZ

Do you have a video? I experienced the rice crispier sounds.. still therr

I don't think my phone's mic will catch that sound, but I'll try. The more I hear it the more it sounds like a loose exhaust shield for sure.

zenben · 10-13-2016, 10:45 AM

Quote:

Originally Posted by Albert88

I don't think my phone's mic will catch that sound, but I'll try. The more I hear it the more it sounds like a loose exhaust shield for sure.

Put the phone in the cup holder. You'd be surprised how much it picks up. My video is what finally got my dealership engaged to solve the noise mystery.

09-25-2016, 12:46 PM	#1
Albert88 Drives: 2015 Camaro LS V6 Join Date: Sep 2016 Location: Los Angeles Posts: 13	Hissing sound - not quite an exhaust leak type sound Hi All. Got my 2015 Camaro LS Manual about 2 weeks ago, love the car. I've noticed that while accelerating I hear a hissing type sound after about 3K RPM. This doesn't sound like an exhaust leak, it sounds different...like a combination of exhaust leak, and an exaggerated sound of liquid being sprayed at high pressure. Couldn't think of a better way to explain it. Do any of the V6 guys hear the same type of noise when accelerating, or do you hear pure exhaust? If it helps, the sound is coming directly from where the engine is sitting.

09-26-2016, 12:52 PM	#2
zenben Drives: 2015 2LT Join Date: Aug 2014 Location: New York Posts: 71	I have two things for you. I have been chasing these types of things for the last 18 months on my 2 year old 2015 2LT RS manual. 1] The first sound was a snap-crake-pop rice-krispies kind of sound that comes from the glove box area. Based on what I have read this is something related to how coolant moves through the heater core. My dealership at one point removed the debris filter for the coolant and that seemed to eliminate this periodic sound for about 600 miles...but then it came back. My dealership said they bypassed the heater core and experienced the same sound. I'd have to see what they did with my own eyes...but since the sound didn't go away, they said this is "normal operation noise". 2] The second more annoying sound is a metal rattle, hiss, chatter sound that comes from the center tunnel area/behind the mylink screen. It happens at 3200RPM and 51MPH most of the time. Also whenever accelerating in most gears, as the RPM's sweep up through the 3000 area it will briefly make this sound. The dealer SUCCESSFULLY found that it is heat shield material way up and in underneath the car near the floorboard that is resonating when the car is making vibrations in that 3000-3300 RPM zone. It is the same type of corrugated-looking-silver-aluminum foil color material that you can see when looking under the hood that is attached to the engine bay. They tapped around all over underneath the car and found pieces that when tapped made a very similar vibration sound as what they heard when we went for a road-test together. They said the pieces they adjusted are very hard to reach...not reality visible. They repositioned pieces and I am quite happy now. It's rare for the sound to occur and now it only happens a bit sometimes in 4th gear and in a much more narrow speed range. The sound has also moved a bit more towards the driver and away from the center telling me that they are definitely adjusting the right materials. Not nearly as constant as it used to be. The car sounded like garbage when accelerating having this rattle chatter sound overshadowing the engine coming to life. IT's pretty darn great now!! My dealership, Arroway Chevrolet in Mt Kisco NY is fantastic!!

09-26-2016, 01:33 PM	#3
zenben Drives: 2015 2LT Join Date: Aug 2014 Location: New York Posts: 71	In one of my visits, they did discover that there was a broken weld on a heat shield attached to my left side Cat. So they replaced the left side cat...but most of my noise was coming from the right so that didn't fix it. I can tell you from what the head of the service department said...who was the one who actually finally put his hands on the car to make the adjustments said the shields he adjusted were way up underneath the car...not part of any pathway that exhaust or cats occupied. They had previously on like 4 other visits adjusted all of those numerous times not leading to a fix.

09-26-2016, 07:54 PM	#4
rnikolich rnikolich9 Drives: 2013 Chevy Camaro 2LT/RS black auto Join Date: Jun 2012 Location: Chicago, IL Posts: 14 View My Garage	I have this noise on my A6 as well. At first I thought it was something wrong with the gears in the transmission, but I assumed it was the heat shield around the transmission tunnel area because the car runs perfectly and I only hear it under harder acceleration or when messing with the paddles.

09-26-2016, 08:35 PM	#5
zenben Drives: 2015 2LT Join Date: Aug 2014 Location: New York Posts: 71	It's the worst sound!! It makes the car sound like garbage! I had some 4 cylinder sedan for a rental recently and admired how when I accelerated all I heard was it's engine, anemic as it was. But Now that mine seems to be fixed it's like having a brand new car again. I'm lucky I had a committed service department that didn't shoo me away.

09-27-2016, 01:57 PM	#7
Albert88 Drives: 2015 Camaro LS V6 Join Date: Sep 2016 Location: Los Angeles Posts: 13	Car has been dropped off the to dealer...if they can't figure it out I'll print out this thread and hand it over. Especially the video of the turbo.

09-30-2016, 08:49 PM	#9
Albert88 Drives: 2015 Camaro LS V6 Join Date: Sep 2016 Location: Los Angeles Posts: 13	Dealer said they couldn't reproduce the sound. I told them the tech needs better hearing aids. The sound is very clear and very present. I'll try again on the next oil change. My only issue is that they drove the car for 10 miles and did "hard accelerations" to try to reproduce the sound....They'll have to do it again. This time w/ me in the car.

10-10-2016, 05:58 PM	#10
BLURPLE2 Drives: 2014 Blue Ray Metallic 2LS Join Date: Mar 2016 Location: Warrenton Posts: 13	I have this hiss on my '14 V6 automatic after getting up over 3K RPM. I had a small confirmed leak on the passenger side at the clamp just after the cat. replaced it and didn't hear the hiss for a few days but its back. gotta get it back up in the air and recheck..