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Old Jun 20, 2022 | 02:45 PM
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Default Rough Idle

5,500 miles. 2017 LT1 GS.
The idle is slightly rough. I can feel it in my seat, and the passenger can also feel in the the seat of their pants.
Any Ideas ?

Still runs fine all the way to 6,000 RPM. Ran it at the track, runs amazing.
What would cause a very slight idle roughness ?
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Old Jun 20, 2022 | 02:54 PM
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They are like that from new. Camshaft design.
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Old Jun 20, 2022 | 03:00 PM
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my 2017 stingray does the same thing its normal and just the way the engine is some would refer to it as camshaft lope LSA (lobe separation angle) determines the choppiness, it has to do with the overlap of when both valves are open, as in when the exhaust valve is closing and the intake valve is opening to pull fresh fuel in on the intake stroke after pushing out the burnt fuel.
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Old Jun 29, 2022 | 08:56 PM
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It's intentional so we can pretend they're real performance cars! (okay, just a joke; but the truth is the cam specs don't see all that radical)
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Old Jun 30, 2022 | 04:14 PM
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I don't believe it is the cam either-[-It is just not lopey to me at all or rough idling
My suggestion would be to take it to a tuner---that can data log certain items OR even to any shop that has a TECH II device or something similar
1st List all or any of the mods you have installed
Most likely culprits are LTFT fuel trims that have become way off --usually due to a CAI or aftermarket exhaust or LT headers
Also have any shop do an "IDLE RELEARN PROCEDURE "
Make sure your LTFT fuel trims are "0" or slightly negative----Never positive
That can only be corrected with a tuning device using your MAF table
While there also have a tuner raise the "Warmed idle" from 650 to 700 RPM's--this will also smooth the idle greatly
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Old Jun 30, 2022 | 05:03 PM
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Tech 2 does not work on C7. At all.
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Old Jun 30, 2022 | 08:33 PM
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They all idle a little bit rough; I have GDS2 and HP Tuners ... and see absolutely nothing wrong but mine does not idle smooth, its not Lopey like a big cam, just a little bit rough at idle , my C6 was the same way , its not going to idle like a Ford Taruis
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Old Jun 30, 2022 | 08:34 PM
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Originally Posted by the blur
5,500 miles. 2017 LT1 GS.

What would cause a very slight idle roughness ?
Normal ......
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Old Jul 1, 2022 | 06:27 PM
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Originally Posted by Jeff V.
Tech 2 does not work on C7. At all.
" or something similar "
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Old Jul 21, 2022 | 10:37 PM
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I was wondering about that.
Having come from 2019 & 2021 Camaros with the same engine, they never idled this rough so consistently. There have been times I expected a CEL. I was beginning to wonder if someone had loaded a tune in it, especially since my skip shift is missing, completely.
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Old Jul 24, 2022 | 03:13 PM
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Wouldn't hurt to check the spark plugs and wires. I have seen that causing issues.
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Old Jul 24, 2022 | 06:50 PM
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Originally Posted by Dusty RoadZ
I was wondering about that.
Having come from 2019 & 2021 Camaros with the same engine, they never idled this rough so consistently. There have been times I expected a CEL. I was beginning to wonder if someone had loaded a tune in it, especially since my skip shift is missing, completely.
If your skip is missing..its tuned.

However if the idle was fine or not how it is now, check your plugs wires, and O2's. These GEN V are pretty sensitive to changes and have to be just right.
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Old Sep 7, 2022 | 07:40 PM
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Default Cam idle

Do all c7 level 2 cams have rough idle issues when the ac is on. Doesn’t idle right all of the time.
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Old Sep 7, 2022 | 09:07 PM
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Originally Posted by Chaggy2
Do all c7 level 2 cams have rough idle issues when the ac is on. Doesn’t idle right all of the time.
mine idles the same with air on or with air off. Shakes just a bit . No worse than my C6 LS3. It idled the same.

Dave
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Old Sep 7, 2022 | 09:54 PM
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Default C7 idle

Originally Posted by Dcasole
mine idles the same with air on or with air off. Shakes just a bit . No worse than my C6 LS3. It idled the same.

Dave
Appreciate it Dave. Have a nice night
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