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

Gen5_AK · 10-04-2022, 09:29 AM

As the title states, how much shudder at idle is there?

This is my first car like this and I'm wondering if it's simply something due to the larger engine, or should there be zero physical shuddering at all?

The RPMs don't move up or down like it's searching for a spot to idle. Sits at 750rpms and doesn't really move. But, the car physically moves enough that I can see the hood rolling side to side. Not a constant shudder, like a shake shake shake, smooth, smooth, smooth, smooth, shake shake shake. If that makes sense.

I did buy this used with 64,000 miles - and as far as I know the only modifications were deleting the mufflers. Which has a great deal amount popping on deceleration, is this an indication of mods beyond this?

I assume a safe spot to start would be changing the spark plugs.

Anything else that I should check?

TooCool5 · 10-04-2022, 08:05 PM

Could also try a fuel cleaner additive that removes water, that can make a shudder as the ECU tries to correct.
Also do a fuse pull of 5 & 20. to re set the fuel tables.
Could be stuck on low octane tables.

Gen5_AK · 10-05-2022, 10:18 AM

Quote:

Originally Posted by TooCool5

Could also try a fuel cleaner additive that removes water, that can make a shudder as the ECU tries to correct.
Also do a fuse pull of 5 & 20. to re set the fuel tables.
Could be stuck on low octane tables.

I will do both of those things! Really appreciate the response.

1JEWLDSSRS · 10-05-2022, 07:04 PM

As far as the shaking you are experiencing, it could be just the nature of the beast. I have learned over the many years of being on this forum, and owning my Camaro that these engines, the LS3 if it is a manual, and the L99 if it is an auto, do have what all the guys refer to as the "LS SHAKE"... It is normal for these engines. It is the cam these engines have in them. If it were anything major, like a misfire or something, you would be getting a CEL, and a code stored in your ECU.. As for the popping when decelerating being loud, no mufflers, it will be loud. It is what they call DFCO, or deceleration fuel cutoff, and it causes the exhaust to pop and crackle upon slowing down. Normal operation.

Gen5_AK · 10-06-2022, 11:12 AM

Quote:

Originally Posted by 1JEWLDSSRS

As far as the shaking you are experiencing, it could be just the nature of the beast. I have learned over the many years of being on this forum, and owning my Camaro that these engines, the LS3 if it is a manual, and the L99 if it is an auto, do have what all the guys refer to as the "LS SHAKE"... It is normal for these engines. It is the cam these engines have in them. If it were anything major, like a misfire or something, you would be getting a CEL, and a code stored in your ECU.. As for the popping when decelerating being loud, no mufflers, it will be loud. It is what they call DFCO, or deceleration fuel cutoff, and it causes the exhaust to pop and crackle upon slowing down. Normal operation.

Awesome info! No codes. No anything. Never been in another LS3, but this certainly is the fastest vehicle I've owned - I say that to say, it feels like it's running fine.

Greatly appreciate the response! 😁

1JEWLDSSRS · 10-06-2022, 06:42 PM

Quote:

Originally Posted by Gen5_AK

Awesome info! No codes. No anything. Never been in another LS3, but this certainly is the fastest vehicle I've owned - I say that to say, it feels like it's running fine.

Greatly appreciate the response! 😁

You are most welcome sir!! Drive it and enjoy it. Just make sure to use top tier fuel at least 91-93 octane...

Gen5_AK · 10-07-2022, 01:46 PM

Quote:

Originally Posted by 1JEWLDSSRS

You are most welcome sir!! Drive it and enjoy it. Just make sure to use top tier fuel at least 91-93 octane...

Sadly, the highest fuel we can get is 90 😞

1JEWLDSSRS · 10-09-2022, 10:27 AM

Well if that's all you have, 90 works as well. Just NEVER put 87 in that thing. Unless you have a V6 that is designed to use 87..

10-04-2022, 09:29 AM	#1
Gen5_AK Drives: 2011 Camaro SS 2SS LS3 Join Date: Sep 2022 Location: Alaska Posts: 18	Idle Shudder As the title states, how much shudder at idle is there? This is my first car like this and I'm wondering if it's simply something due to the larger engine, or should there be zero physical shuddering at all? The RPMs don't move up or down like it's searching for a spot to idle. Sits at 750rpms and doesn't really move. But, the car physically moves enough that I can see the hood rolling side to side. Not a constant shudder, like a shake shake shake, smooth, smooth, smooth, smooth, shake shake shake. If that makes sense. I did buy this used with 64,000 miles - and as far as I know the only modifications were deleting the mufflers. Which has a great deal amount popping on deceleration, is this an indication of mods beyond this? I assume a safe spot to start would be changing the spark plugs. Anything else that I should check?

10-04-2022, 08:05 PM	#2
TooCool5 Drives: 2010 Camaro 1LS 3.6 LLT V6 325 HP Join Date: May 2009 Location: LS Posts: 4,242 View My Garage	Could also try a fuel cleaner additive that removes water, that can make a shudder as the ECU tries to correct. Also do a fuse pull of 5 & 20. to re set the fuel tables. Could be stuck on low octane tables. __________________ 2010 Camaro Auto, Inferno Orange, Titanium Interior, Gearhead Wheels AIRAID CAI

10-05-2022, 07:04 PM	#4
1JEWLDSSRS Drives: 2011 SS-RS Join Date: May 2011 Location: FLORIDA Posts: 11,442	As far as the shaking you are experiencing, it could be just the nature of the beast. I have learned over the many years of being on this forum, and owning my Camaro that these engines, the LS3 if it is a manual, and the L99 if it is an auto, do have what all the guys refer to as the "LS SHAKE"... It is normal for these engines. It is the cam these engines have in them. If it were anything major, like a misfire or something, you would be getting a CEL, and a code stored in your ECU.. As for the popping when decelerating being loud, no mufflers, it will be loud. It is what they call DFCO, or deceleration fuel cutoff, and it causes the exhaust to pop and crackle upon slowing down. Normal operation. __________________ TSP STAGE 3 CAM,231/246 @112 LSA 614/641 LIFT, CIRCLE D 5C-4200-4500 CONVERTER,LOD INTAKE.CORSA EXHAUST. DSS 1 PC DS. PEGASUS SOLID CRADLE MOUNTS. 486RWHP/475RWTQ.LOTS MORE.

10-09-2022, 10:27 AM	#8
1JEWLDSSRS Drives: 2011 SS-RS Join Date: May 2011 Location: FLORIDA Posts: 11,442	Well if that's all you have, 90 works as well. Just NEVER put 87 in that thing. Unless you have a V6 that is designed to use 87.. __________________ TSP STAGE 3 CAM,231/246 @112 LSA 614/641 LIFT, CIRCLE D 5C-4200-4500 CONVERTER,LOD INTAKE.CORSA EXHAUST. DSS 1 PC DS. PEGASUS SOLID CRADLE MOUNTS. 486RWHP/475RWTQ.LOTS MORE.