Uneven Idle? - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

PalmerGA · 08-08-2012, 08:55 PM

When I first start my 1LT (when it's cold) the idle is uneven. It kind of fluctuates up and down and misses ever so slightly. This lasts about 30 seconds and then it smooths right out. Happens every time when cold (like when it has sat for 5+ hours or so).

Anyone else have this issue and know what it might be? I'm hoping the new Throttle Body may eliminate it, but that will be a while getting here.

Any help is much appreciated.

D-RockSS12 · 08-08-2012, 08:57 PM

It's normal

PalmerGA · 08-08-2012, 08:59 PM

Really? That's odd... but good to know. Thanks.

JohnnyBfromPeoria · 08-08-2012, 09:16 PM

Mine does it too.

John B.

HP Turbine · 08-08-2012, 09:31 PM

On a cold start your car will idle at a higher RPM to warm up your fluids, then it drops down to a regular idle. It's a noticeable sound difference. I guess it could be perceived as uneven?

Henry G. · 08-08-2012, 09:31 PM

Me too.

Lil' Nasty · 08-08-2012, 10:57 PM

Normal

awfarley · 08-08-2012, 11:45 PM

I've heard they run really rich at first and mine does that too. Something about the cats I believe...

awfarley · 08-08-2012, 11:48 PM

Quote:

Originally Posted by HP Turbine

On a cold start your car will idle at a higher RPM to warm up your fluids, then it drops down to a regular idle. It's a noticeable sound difference. I guess it could be perceived as uneven?

Yeah the high idle is normal too, but the OP is referring to a definitive 'shake' in the car. (At least I think) It almost feels like a single cylinder misfire only not quite as vigorous. I was worried when I first noticed it too but someone said it was almost like a purge of some sort for the engine but I will admit I have no idea what it does or why lol

HP Turbine · 08-09-2012, 01:49 AM

Quote:

Originally Posted by awfarley

Yeah the high idle is normal too, but the OP is referring to a definitive 'shake' in the car. (At least I think) It almost feels like a single cylinder misfire only not quite as vigorous. I was worried when I first noticed it too but someone said it was almost like a purge of some sort for the engine but I will admit I have no idea what it does or why lol

I'll give my morning start my full attention today and see what's up.

Maybe there is a small vacuum leak?

PalmerGA · 08-09-2012, 05:46 AM

I appreciate the input. Mine is not just a higher idle - I know that is typical in just about all vehicles. When I crank it this morning I'll pay closer attention but, I'm pretty sure the RPMs kind of surge up and down for 30 seconds or so before dropping down to normal idle.

There is nothing I would classify as a "shake", awfarley. A tiny bit of "spittin' and sputterin'", perhaps.

nyrfan · 08-09-2012, 06:46 AM

Had the same problem, added an RX breather and that somehow corrected the problem (Tracy explains why), read this post:

http://www.camaro5.com/forums/showthread.php?t=221773

awfarley · 08-09-2012, 08:54 AM

Quote:

Originally Posted by PalmerGA

I appreciate the input. Mine is not just a higher idle - I know that is typical in just about all vehicles. When I crank it this morning I'll pay closer attention but, I'm pretty sure the RPMs kind of surge up and down for 30 seconds or so before dropping down to normal idle.

There is nothing I would classify as a "shake", awfarley. A tiny bit of "spittin' and sputterin'", perhaps.

Hmmm.... maybe you have a real problem then. I've just heard many people talk about similiar things with the LFX.

PalmerGA · 08-09-2012, 10:29 AM

Quote:

Originally Posted by awfarley

Hmmm.... maybe you have a real problem then. I've just heard many people talk about similiar things with the LFX.

Yeah, well I'm sure it isn't harmful and matbe the Ported TB will help. I may go ahead and get a Rx Breather as nyrfan suggests. Thanks for your input.

08-08-2012, 08:55 PM	#1
PalmerGA Drives: 2013 SIM 1SS/RS L99 Join Date: May 2012 Location: Southwest GA Posts: 8,755 View My Garage	Uneven Idle? When I first start my 1LT (when it's cold) the idle is uneven. It kind of fluctuates up and down and misses ever so slightly. This lasts about 30 seconds and then it smooths right out. Happens every time when cold (like when it has sat for 5+ hours or so). Anyone else have this issue and know what it might be? I'm hoping the new Throttle Body may eliminate it, but that will be a while getting here. Any help is much appreciated. __________________ 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)

08-08-2012, 08:59 PM	#3
PalmerGA Drives: 2013 SIM 1SS/RS L99 Join Date: May 2012 Location: Southwest GA Posts: 8,755 View My Garage	Really? That's odd... but good to know. Thanks. __________________ 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)

08-08-2012, 09:16 PM	#4
JohnnyBfromPeoria Drives: 2012 LS M6, Black Join Date: May 2009 Location: Phoenix, AZ Posts: 2,045	Mine does it too. John B. __________________ 12 LS M6, IPF S/C, ASA GT-5 wheels, VMax PTB 1995 Mitsubishi Montero SR 1987 Dodge Raider Turbo Project 1986 Mitsubishi Montero 2.4l FI Transplant

08-08-2012, 09:31 PM	#5
HP Turbine Boosted Drives: 2012 1LT RS... with snails Join Date: May 2012 Location: New Hampshire Posts: 1,455 View My Garage	On a cold start your car will idle at a higher RPM to warm up your fluids, then it drops down to a regular idle. It's a noticeable sound difference. I guess it could be perceived as uneven? __________________ IPS Twin Turbos, Corsa Exhaust, Ported Throttle Body. 461 rwhp 443 rwtq!! Cameron Hass.ani

08-08-2012, 10:57 PM	#7
Lil' Nasty [COTW 4/13/15] Drives: Supercharged LLT Join Date: Jul 2010 Location: Florida Posts: 5,957	Normal __________________ LiL' Nasty's Build Journal

08-08-2012, 08:57 PM	#2
D-RockSS12 I like money Drives: Black 2012 Camaro 1SS/RS, Bitchin Join Date: Feb 2012 Location: Redwood City, CA Posts: 73 View My Garage	It's normal

08-08-2012, 09:31 PM	#6
Henry G. Drives: 2012 Camaro LFX,CAI,DynomaxVT,RX CC Join Date: Feb 2012 Location: So Cal Mtns Posts: 526	Me too.

08-08-2012, 11:45 PM	#8
awfarley Drives: 2011 5.7L Tundra Double-Cab X-SP Join Date: Mar 2012 Location: Birmingham, AL Posts: 2,031	I've heard they run really rich at first and mine does that too. Something about the cats I believe...

08-09-2012, 05:46 AM	#11
PalmerGA Drives: 2013 SIM 1SS/RS L99 Join Date: May 2012 Location: Southwest GA Posts: 8,755 View My Garage	I appreciate the input. Mine is not just a higher idle - I know that is typical in just about all vehicles. When I crank it this morning I'll pay closer attention but, I'm pretty sure the RPMs kind of surge up and down for 30 seconds or so before dropping down to normal idle. There is nothing I would classify as a "shake", awfarley. A tiny bit of "spittin' and sputterin'", perhaps. __________________ 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)

08-09-2012, 06:46 AM	#12
nyrfan Let's go Rangers! Drives: 13' AGM 2SS/RS L99 Join Date: Jun 2011 Location: Orlando, FL Posts: 10,742 View My Garage	Had the same problem, added an RX breather and that somehow corrected the problem (Tracy explains why), read this post: http://www.camaro5.com/forums/showthread.php?t=221773 __________________ Soprano 4/1/00-6/14/11, Gone but NEVER forgotten! FSP tuned: 377/389