[wbcamaro6]

Hello all, could anybody give me insight on what’s going on ? The car has 55k on the odo but everything mechanically and electrically checks out the only issue is every now and again when idling in the car I can feel the engine vibrate/ pulse a little hard I was thinking maybe the engine mounts… if you can help it would be much appreciated

[Camaro fanboy]

my 8k milage v8 is the same. i think it's normal. i did run a can of injector cleaner through the gas tank and it helped a little.

[FlukeSS]

Originally Posted by wbcamaro6

Hello all, could anybody give me insight on what’s going on ? The car has 55k on the odo but everything mechanically and electrically checks out the only issue is every now and again when idling in the car I can feel the engine vibrate/ pulse a little hard I was thinking maybe the engine mounts… if you can help it would be much appreciated

You are not alone I have the same exact issue.

When resting at idle, the RPMS drop to 500 then back to 600 where my idle point is supposed to be. It does this intermittently, doesn't matter if the engine is cold or at running temp.

Mostly does it when the engine is warming up. I can feel it when it happens, and even the idle resonance of the engine changes.

I was going to post about it and I do have a video of it.

Issue occurs at the beginning of the video within the first 8 seconds

[wbcamaro6]

Originally Posted by Camaro fanboy

my 8k milage v8 is the same. i think it's normal. i did run a can of injector cleaner through the gas tank and it helped a little.

Thank you, I don’t believe it’s serious but it might just be that or worst case a new drive shaft

[wbcamaro6]

Originally Posted by FlukeSS

You are not alone I have the same exact issue.

When resting at idle, the RPMS drop to 500 then back to 600 where my idle point is supposed to be. It does this intermittently, doesn't matter if the engine is cold or at running temp.

Mostly does it when the engine is warming up. I can feel it when it happens, and even the idle resonance of the engine changes.

I was going to post about it and I do have a video of it.

Pending video upload

Same, my does it when it’s warming up but after it’s up to operating temps it’s barely there

[1badtie]

my past 3 GM trucks have done this same thing.

[Camaro fanboy]

Originally Posted by FlukeSS

You are not alone I have the same exact issue.

When resting at idle, the RPMS drop to 500 then back to 600 where my idle point is supposed to be. It does this intermittently, doesn't matter if the engine is cold or at running temp.

Mostly does it when the engine is warming up. I can feel it when it happens, and even the idle resonance of the engine changes.

I was going to post about it and I do have a video of it.

Issue occurs at the beginning of the video within the first 8 seconds

must be normal mine is the same . try a bottle of injector cleaner in the tank. no harm trying. calmed mine down a little

[Chutzpah]

Outside air temp, engine temp, humidity, elevation and fuel source all makes a difference. All three 6th gens have done the same thing to one degree or another, with the ZL1 idling the smoothest of all. I’ve also noticed (or imagined) things smooth out after a bit a extended Italian tune up.

[Camaro fanboy]

yeah i find after a good long hard run it seems to idle better. good clean out as they say.
from googling it's totaly normal. they designed them to be a bit lumpy on idle. check on the vette forums

[LT4Greg]

My 2017 ZL1 is the same way idling until the engine warms up. You don’t have an issue in my opinion.��

[ctrlz]

There are basically two idle scenarios:
1) cold start, open loop idle - the engine runs off a set of maps for given conditions. No feedback from oxygen sensor

2) closed loop idle - when all sensors are warmed up and ECM can rely on their feedback to adjust air/fuel mixture accordingly

If your idle is fluctuating in open loop, no worries. Closed loop idle should be steady.

[FlukeSS]

Originally Posted by Camaro fanboy

yeah i find after a good long hard run it seems to idle better. good clean out as they say.
from googling it's totaly normal. they designed them to be a bit lumpy on idle. check on the vette forums

Same here, after a while it doesn't do it anymore.

[FlukeSS]

Originally Posted by ctrlz

There are basically two idle scenarios:
1) cold start, open loop idle - the engine runs off a set of maps for given conditions. No feedback from oxygen sensor

2) closed loop idle - when all sensors are warmed up and ECM can rely on their feedback to adjust air/fuel mixture accordingly

If your idle is fluctuating in open loop, no worries. Closed loop idle should be steady.

Refer to my video, you can see my operating temp is reached and I still get the issue, but not very often.

I was deciding given the mileage about doing a tune up.

[taylorforschool@gmail.com]

Originally Posted by ctrlz

There are basically two idle scenarios:
1) cold start, open loop idle - the engine runs off a set of maps for given conditions. No feedback from oxygen sensor

2) closed loop idle - when all sensors are warmed up and ECM can rely on their feedback to adjust air/fuel mixture accordingly

If your idle is fluctuating in open loop, no worries. Closed loop idle should be steady.

You sound like you know you’re stuff


Maybe you could tell me why my 6th gear makes a noise and higher gears at cruising under minimal pedal application (just flowing along) one of those higher shifts tends to be very…slow to engage. Actually experience a quick jump of 50-100 rpm right before the drop in RPMs and a hard shift.. I’ve never experienced this small stutter or catch in the gears before.. doesn’t happen in manual paddle shifting. Doesn’t happen under WOT. This is also not the known 3-4 hard shift have been able to verify. Sorry to thread hijack