PLEASE advise ( unnusual sounds ) - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

sakipat · 06-23-2013, 10:28 PM

I'll try and make this short...

I had some parts put in my LS3 about a month ago...
- Intake
- LT Headers
- Exhaust System

I never had a "modded" car before so I didn't know what to expect (other than reading threads here).

So, here are the 2 unusual sounds I've been noticing:

1. When the engine is cold, car sounds like a "fart can" when accelerating ( around 3-4 rpms )

2. When slowing down from a 30-40mph cruise, I hear popping sounds around the exhaust area.. 2 pops.... pause.. then another 2. and so on....

However, when the engine warms up, all is well.

Please Advise. Thank you.

Supercharged SS · 06-23-2013, 10:32 PM

Quote:

Originally Posted by sakipat

I'll try and make this short...

I had some parts put in my LS3 about a month ago...
- Intake
- LT Headers
- Exhaust System

I never had a "modded" car before so I didn't know what to expect (other than reading threads here).

So, here are the 2 unusual sounds I've been noticing:

1. When the engine is cold, car sounds like a "fart can" when accelerating ( around 3-4 rpms )

2. When slowing down from a 30-40mph cruise, I hear popping sounds around the exhaust area.. 2 pops.... pause.. then another 2. and so on....

However, when the engine warms up, all is well.

Please Advise. Thank you.

The slowing down noise is decel popping. You can search about it. Many cars have it. I believe it can be tuned out.

The fart can explanation I have no idea what you're trying to explain. Sorry.

sakipat · 06-24-2013, 01:14 AM

Thank you. I'll record audio tomorrow and post.

txgoose · 02-22-2014, 11:02 AM

This appears to be an old thread, but I too have an unusual sound coming from the back of my car. Seems to be "timed". About 5 minutes after I start my car, I get 5 taps in succession that seem to come from the trunk. No indications that anything is wrong, just "tap,tap,tap,tap,tap". They're faint enough that if I have any throttle going on, I can't hear them, but at a light they're quite noticeable.

banter · 02-22-2014, 11:07 AM

Quote:

Originally Posted by txgoose

This appears to be an old thread, but I too have an unusual sound coming from the back of my car. Seems to be "timed". About 5 minutes after I start my car, I get 5 taps in succession that seem to come from the trunk. No indications that anything is wrong, just "tap,tap,tap,tap,tap". They're faint enough that if I have any throttle going on, I can't hear them, but at a light they're quite noticeable.

My '07 Cobalt did the same thing and I never figured out wtf it was. People would always joke and ask if someone was locked in my trunk. Haven't heard it from my Camaro though.

patternpilot · 02-22-2014, 11:17 AM

Its your exhaust. As it warms up the medal expands and make those noises. Since the pipes are all welded I would think its the mufflers. Should be nothing to worry about.

PalmerGA · 02-22-2014, 04:28 PM

Do you have an automatic? Could be AFM.

stevey_frac · 02-22-2014, 04:44 PM

Quote:

Originally Posted by txgoose

This appears to be an old thread, but I too have an unusual sound coming from the back of my car. Seems to be "timed". About 5 minutes after I start my car, I get 5 taps in succession that seem to come from the trunk. No indications that anything is wrong, just "tap,tap,tap,tap,tap". They're faint enough that if I have any throttle going on, I can't hear them, but at a light they're quite noticeable.

What you are hearing is the evap solenoid going through it's test cycle to make sure it still works. It's normal. Louder on some cars then others.

Dimitrim · 02-22-2014, 04:50 PM

Quote:

Originally Posted by stevey_frac

What you are hearing is the evap solenoid going through it's test cycle to make sure it still works. It's normal. Louder on some cars then others.

On my 2009 Cobalt SS, when I installed the CAI, on cold start up it was loud.

j3ff9ack · 02-22-2014, 10:38 PM

Quote:

Originally Posted by txgoose

This appears to be an old thread, but I too have an unusual sound coming from the back of my car. Seems to be "timed". About 5 minutes after I start my car, I get 5 taps in succession that seem to come from the trunk. No indications that anything is wrong, just "tap,tap,tap,tap,tap". They're faint enough that if I have any throttle going on, I can't hear them, but at a light they're quite noticeable.

Sounds like the fuel system

http://www.camaro5.com/forums/showth...ferrerid=24831

TigerFA · 02-22-2014, 11:04 PM

Quote:

Originally Posted by Supercharged SS

The slowing down noise is decel popping. You can search about it. Many cars have it. I believe it can be tuned out.

The fart can explanation I have no idea what you're trying to explain. Sorry.

even get it with the NPP, like it

06-23-2013, 10:28 PM	#1
sakipat Drives: 2010 Camaro 2SS RS Join Date: Dec 2012 Location: San Diego Posts: 97	PLEASE advise ( unnusual sounds ) I'll try and make this short... I had some parts put in my LS3 about a month ago... - Intake - LT Headers - Exhaust System I never had a "modded" car before so I didn't know what to expect (other than reading threads here). So, here are the 2 unusual sounds I've been noticing: 1. When the engine is cold, car sounds like a "fart can" when accelerating ( around 3-4 rpms ) 2. When slowing down from a 30-40mph cruise, I hear popping sounds around the exhaust area.. 2 pops.... pause.. then another 2. and so on.... However, when the engine warms up, all is well. Please Advise. Thank you.

02-22-2014, 11:17 AM	#6
patternpilot Drives: 2012 2SS/RS Join Date: Aug 2011 Location: Tri-Cities WA. Posts: 928 View My Garage	Its your exhaust. As it warms up the medal expands and make those noises. Since the pipes are all welded I would think its the mufflers. Should be nothing to worry about. __________________ There's more to life than gas mileage LS3, Whipple, Custom Comp Cam, springs, pushrods, timing set, CAI intake, Apex cold air scoop, Doug Thorley TRI-Y headers, Billet Custom Products baffled Valve covers, Mighty Mouse Catch can, ADM FPCM, ZL1 fuel pump, MSD boost-a-pump, Hex Vent hood vents, ProSport gauges(fuel pressure, AFR, Boost), Corsa, 100 cell Cats. Jannetty remote tuned, Pfadt trailing arms, all parts user installed. No Dyno yet. Manual trans. 3.45 gears.

02-22-2014, 04:28 PM	#7
PalmerGA Drives: 2013 SIM 1SS/RS L99 Join Date: May 2012 Location: Southwest GA Posts: 8,755 View My Garage	Do you have an automatic? Could be AFM. __________________ 2013 1SS/RS Coupe L99, Stainless Power Works LT Headers, SCT X4 Custom Tune from RDP, CAI Inc. Air Intake w/ Apex Scoop, VMAX CNC Ported Throttle Body, Solo Axle-Back Exhaust w/ J-pipes, Apex Catch Can, Husky Splash Guards, Heritage Grille, 3D Carbon Rear Spoiler, Oracle Chrome Turn Signal Bulbs, GM Reverse Light Trim Billets, Gorilla Black Locking Lugs, Emblem Pros Retro SS Badges/Custom Retro SS Kickplates/Under-hood Bowtie, 35% window Tint, Nitto Motivo Tires (6-8-18)

06-24-2013, 01:14 AM	#3
sakipat Drives: 2010 Camaro 2SS RS Join Date: Dec 2012 Location: San Diego Posts: 97	Thank you. I'll record audio tomorrow and post.

02-22-2014, 11:02 AM	#4
txgoose Drives: 2010 VR 2SS/RS Join Date: May 2012 Location: San Antonio, TX Posts: 66	This appears to be an old thread, but I too have an unusual sound coming from the back of my car. Seems to be "timed". About 5 minutes after I start my car, I get 5 taps in succession that seem to come from the trunk. No indications that anything is wrong, just "tap,tap,tap,tap,tap". They're faint enough that if I have any throttle going on, I can't hear them, but at a light they're quite noticeable.